A recursive rule for a geometric sequence:
[tex]a_1\\\\a_n=r\cdot a_{n-1}[/tex]
---------------------------------------------------
[tex]a_1=27;\ a_2=9;\ a_3=3;\ a_4=1;\ ...\\\\r=\dfrac{a_{n+1}}{a_n}\to r=\dfrac{a_2}{a_1}=\dfrac{a_3}{a_2}=\dfrac{a_4}{a_3}=...\\\\r=\dfrac{9}{27}=\dfrac{1}{3}\\\\\boxed{a_1=27;\qquad a_n=\dfrac{1}{3}\cdot a_{n-1}}[/tex]
Please help ASAP!
What is the value of cosθ given that (−5, −4) is a point on the terminal side of θ ?
A). 5√41/41
B). −4√41/41
C). 4√41/41
D). −5√41/41
Answer:
D
Step-by-step explanation:
The value of the trigonometric expression cos θ, when (-5, -4) is a point on the terminal side of θ is -5√41/41. Hence, option D is the right choice.
What are trigonometric expressions?
Trigonometric expressions are the ratios of the sides of a right triangle, which are always constant despite the increase or decrease in the size of its sides.
These are the trigonometric ratios:
sin θ = perpendicular/hypotenusecos θ = base/hypotenusetan θ = sin θ/cos θ = perpendicular/basecot θ = 1/tan θ = cos θ/sin θ = base/perpendicularsec θ = 1/cos θ = hypotenuse/basecosec θ = 1/sin θ = hypotenuse/perpendicular.How to solve the question?In the question, we are asked to find the value of cos θ, given that (-5, -4) is a point on the terminal side of θ.
This means that we; are in quadrant III. As we know, cos θ is negative in the 3rd quadrant.
The base is the distance of the x-coordinate from the origin, that is, 5 units.
The perpendicular is the distance of the y-coordinate from the origin, that is, 4 units.
By Pythagoras' Theorem,
Hypotenuse² = Base² + Perpendicular²,
or, Hypotenuse² = 5² + 4²,
or, Hypotenuse² = 25 + 16,
or, Hypotenuse = √41.
As we know, cos θ = Base/Hypotenuse = 5/√41 = 5√41/41.
Because of the 3rd quadrant, we will take, cos θ = - 5√41/41.
Thus, the value of the trigonometric expression cos θ, when (-5, -4) is a point on the terminal side of θ is -5√41/41. Hence, option D is the right choice.
Learn more about trigonometric expressions at
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1. What is the radical form of the expression 4 2/3?
2. What function equation is represented by th graph?
Answer:
1. [tex]\sqrt[3]{4^2}[/tex]
2. Answer A
Step-by-step explanation:
1. A fraction exponent can be represented using a radical. The base number is the number in the radical. The numerator of the fraction is the exponent inside the radical. The denominator is the type of radical.
[tex]4^{\frac{2}{3} }[/tex]
[tex]\sqrt[3]{4^2}[/tex]
2. An exponential always crosses at (0,1) This function crosses at (0.6) meaning it has shifted up 5 units or +5. These means only answer options A and D are possible solutions. Also, since the graph starts high and ends low and leveling out, this means the base is less than 1. Only 3/4 is less than 1. Answer A is the solution.
Given h(x)=5(x-6)^2+2 what transformations were done compared to the parent function f(x)=x^2?
Answer:
1. Translation 6 units to the right.
2. Stretch by a factor 5.
3. Translation 2 units up.
Step-by-step explanation:
Consider parent function [tex]f(x)=x^2.[/tex]
1. Translate the graph of the function 6 units to the right. Then you get the function [tex]f_1(x)=(x-6)^2.[/tex]
2. Stretch the graph of the function [tex]f_1(x)=(x-6)^2[/tex] by a factor 5 and get the function [tex]f_2(x)=5(x-6)^2.[/tex]
3. Translate the graph of the function [tex]f_2(x)=5(x-6)^2[/tex] 2 units up to fet the function [tex]h(x)=5(x-6)^2+2.[/tex]
Brooke has to set up 70 chairs in equal rows for the clas talent show. But, there is not room for more than 20 rows. What are the possible number of rows that Brooke could set up?
A square lawn is surrounded by a path 2.5 m wide . If the area of the path is 165 m sq, find the area of the lawn
heyyy help pls with pciutreeeee
Answer:
12 Fetches
Step-by-step explanation:
this one is easy but you probably overthought it,
since 2 is half of 4 then you would just multiply everything by 2
let's just say that didn't work right, for these types of problems you have to make a proportion so in this case it would be 2 minutes/6 fetches= 4 minutes/ x fetches. then you solve by cross multiplication.
Sara drives 425 miles in 6 hours and 45 minutes. What is her average rate of speed? Round your answer to the nearest whole number.
Answer: 63 miles per hour (mph)
6 hours + 45 minutes = 6 hrs + 0.75 hrs = 6.75 hrs
Divide the distance (425 miles) over the time (6.75 hours) to get the speed. You must convert the time value to a single unit rather than a mixed unit of hours and minutes. So we get 425/6.75 = 62.96926 which rounds to 63
PLEASE HELP. WILL GIVE BRAINIEST AND 60 POINTS if you show work so I can understand these.
1. Find the slope of the line that passes through the
points (-1, 2), (0, 5).
2. Suppose y varies directly with x, and y = 15 and x = 5.
Write a direct variation equation that relates x and y.
What is the value of y when x = 9?
3. Write an equation in slope-intercept form of the line
that passed through (-3, 4) and (1. 4).
4. Use point-slope form to write the equation of a line
that has a slope of 2/3
and passes through (-3, -1).
Write your final equation in slope-intercept form.
5. Write the equation in standard form using integers
(no fractions or decimals): = −2/3 − 1
6. Write an equation of the line that passes through
(2, -1) and is parallel to the graph of y = 5x – 2. Write
your final equation in slope-intercept form.
7. Write an equation of
1) use change in y/change in x to find the slope from two points:
change in y: 5-2=3
change in x: 0-(-1)=1
3/1=3 is your slope
2) if it is a direct variation, you know as x increases, y increases, both at constant rates
since y is 10 more than x in the example, it will always be 10 more than x
y=x+10 is your equation.
when x=9, y=19
now they could not be reffering to their difference in addition, but their difference in multiplication. In that case, y is 3 times x in the example, so it will always be 3 times x
y=3x is your equation
when x=9, y=27
3) the slope of this line is determined by change in y over change in x:
change in y: 4-4=0
you don't need to calculate the change in x because 0 divided by anything is 0, so that is your slope.
y=0x+b
4=0(1)+b
4=0+b
4=b
y=4 is your equation because 0 times x is zero. this means that it is a horizontal line with a constant y value of 4
4)
y - value of y in a point =slope (x - value of x in a point)
y-(-1)=2/3 * (x-(-3))
y+1=2/3x+2/3(3)
y+1= 2/3x+2
y=2/3x+1
from solving point slope form, you can get to slope intercept form
5) not sure what this question is asking for
- a line?
- an expression equivalent to -1 and 2/3?
both of those aren't possible with the information given
6) parallel means same slope different y intercept
y=5x+b
-1=5(2)+b
-1=10+b
-11=b
y=5x-11
The bus comes at 6:55. It takes meg 19 minutes to get to the bus stop. What time would she have to leave at to catch the bus?
Answer:
6 hrs 36 mins
Step-by-step explanation:
Bus at 6:55
Minutes to get to the bus 19.
deduct 19 Minutes from 6:55 = 6 hrs 36 mins
The matrix shows the number of different basketball shots three players made in two minutes. These players want to double these results. Which matrix shows what the players want to do?
Answer:
B
Step-by-step explanation:
Javi [5 1]
Victor [3 2]
Chris [4 2]
A.
[10 1]
[6 2]
[8 2]
B.
[10 2]
[6 4]
[8 4]
C.
[7 3]
[5 4]
[6 4]
D.
[10 1]
[3 2]
[4 2]
Answer:B. [10 2]
[6 4]
[8 4]
Step-by-step explanation:
Javi [5 1]
Victor [3 2]
Chris [4 2]
A.
[10 1]
[6 2]
[8 2]
B.
[10 2]
[6 4]
[8 4]
C.
[7 3]
[5 4]
[6 4]
D.
[10 1]
[3 2]
[4 2]
Explanation:
As a general rule, to double, triple or as the case may be, the result of a matrix, we apply what is known in Maths as scalar multiplication.
Scalar multiplication seeks to multiply the entries in a matrix by a scalar. The resulting matrix is called the scalar product of the original matrix.
For instance:
Let matrix A = [a b] [c d] and k be a scalar.
The matrix kA is called a scalar product of the matrix, A and the constant, k is defined as:
kA = k [a b] [c d]
= [ka kb] [kc kd]
So, for the given question, the best option would be the matrix that depicts a scalar multiple of 2 of the original matrix entry. Option B.
I.e:
Javi = 2[5 1] = [2*5 2*1] = [10 2]
Victor= 2[3 2] = [2*3 2*2] = [6 4]
Chris = 2[4 2] = [2*4 2*2] = [8 4]
Which is the graph of the line with equation:
y + 4 = 2(x−1)
Answer:
The graph in the first picture which intercepts the y-axis at (0,-6) and has a positive slope of 2.
Step-by-step explanation:
We can write the linear equation into slope-intercept form. We do this by simplifying and isolating y.
y+4=2(x-1)
y+4=2(x)-2(1)
y+4=2x-2
y+4-4=2x-2-4
y=2x-6
In y=mx +b form, we can connect the equation to the graph. This equation has b=-6 or (0,-6) for the y-intercept. It also has m=2 for the slope. This is the first graph.
Kristy asks Lonnie to think of a number, and 3 to it, multiply the sum by 2, and then subtract 6. Let n stand for Lonnie's starting numbers. Which expression represents Lonnie's final number?
Answer:
2(n + 3) - 6 is the expression that represents the final number.
Step-by-step explanation:
-Given the number Lonnie thinks of at the beginning is 'n'-
1) adding 3 to n
sum = n + 3
2) multiply the sum by 2
sum = 2(n + 3)
3) subtract 6
sum = 2(n + 3) - 6.
Answer: 2(n + 3) - 6
Step-by-step explanation:
Under a dilation, the point (2, 6) is moved to (6, 18).
What is the scale factor of the dilation?
Divide the new X value by the original x value:
6 / 2 = 3
Then check that with the Y value:
Original Y value = 6, 6 x 3 = 18, which is the new Y value.
This means the scale factor is 3.
Tommy notices that he reads 2/3 page in a minute. At the rate, how long will it take him to read 12 pages
Answer:
18 minutes
Step-by-step explanation:
To do this, you need to divide 12 by the two thirds to find out how many 2/3 there are in 12, giving the amount of minutes it takes:
12 ÷ 2/3 = 18
So it would take him 18 minutes!
What is the perimeter of a triangle with the given side lengths? s1 = x + 4 cm s2 = 3x + 1 cm s3 = 7x + 3 cm P = x + cm
Answer:
11x+8 cm = Perimeter
Step-by-step explanation:
A triangle has 3 sides. We add up all three sides to get the perimeter.
s1+s2+s3 = Perimeter
(x+4) +( 3x+1) + (7x+3) = Perimeter
Combine like terms
11x+8 = Perimeter
Answer:
P = 11x + 8 cm
Step-by-step explanation:
The perimeter of a triangle is the sum of the lengths of the three sides.
... P = s1 + s2 + s3
... P = (x +4 cm) +(3x +1 cm) +(7x +3 cm) . . . . substitute for s1, s2, s3
... P = x(1 +3 +7) + cm(4 + 1 + 3) . . . . . . collect terms
... P = 11x + 8 cm
Which person would be eligible to run for president of the United States in the Election of 2020?
A) Susan, born in 1988 in Texas, has lived in Georgia for 15 years
B)George, a naturalized citizen, has lived in New York for 20 years
C) Tiffany, born in 1973 in Nebraska, has lived in the U.S. for 45 years
D)John, a legal immigrant, has lived in the U.S. for 14 consecutive years
Answer:
C. Tiffany, born in 1973 in Nebraska, has lived in the U.S. for 45 years
Step-by-step explanation:
its right bro
Please answer this question!! 41 points and brainliest!
Answer:
x > -3
Step-by-step explanation:
5x+ 7 > 2(x-1)
Distribute the 2 on each side
5x+7 > 2x -2*1
5x+7 > 2x-2
Subtract 2x from each side
5x-2x +7 > 2x-2x-2
3x + 7>-2
Subtract 7 from each side
3x+7-7>-2-7
3x>-9
Divide by 3 on each side
3x/3 >-9/3
x > -3
Answer:
[tex]x>-3[/tex]
Step-by-step explanation:
To solve equations, we use inverse operations. Normally, we use PEMDAS to simplify an equation. To solve it, we use the inverse of each in this order SADMEP. Solving an inequality is the same except for step. When dividing by a negative, the sign of the inequality changes.
We have [tex]5x+7>2(x-1)\\5x+7>2x-2[/tex] in simplified form. We begin by subtracting or adding constants across the equal sign. Then doing the same with the variable terms. We finish by dividing by the coefficient of the variable term.
[tex]5x+7>2x-2\\5x+7-7>2x-2-7\\5x>2x-9\\5x-2x>2x-2x-9\\3x>-9\\x>-3[/tex]
To graph, we draw a number line, draw an open circle at -3.
Since it is not equal to, we do not fill it in. We leave it open. We also draw an arrow to the right of -3
Jina received a $70 gift card for a coffee store. She used it in buying some coffee that cost $7.51 per pound. After buying the coffee, she had $47.47 left on her card. How many pounds of coffee did she buy
Answer: 3 pounds
Step-by-step explanation:
The equation can be set up according to slope form: y=mx+b where x represents cost per round.
$70 = $7.51x + $47.47
Subtract 47.47 to both sides: $22.53 = $7.51x
Divide both sides by 7.51: 3 = x
Answer: 70 - 47.47 = 22.53. She spent $22.53. If one pound is $7.51. And she spent $22.53 = 3.
She bought 3 pounds of coffee. Brainliest is always appreciated. :)
Can someone please help with these 2 math questions? :)
Answer:
4. 8.8 years
5. 8.6 meters
Step-by-step explanation:
4. The process of solving the equation f(x) = g(x) gives rise to a 4th-degree equation. Those are best solved using some sort of machine solver. A graphing calculator is often a good place to start. If you're going to do that anyway, you may as well start with a graphical solution to the question.
A plot of the two curves finds they intersect at about x = 8.8. (See the first attachment.) This avoids the extraneous solutions introduced by the process of eliminating the radical.
___
5. Analytical solution is simpler here, but the graphing calculator is faster yet. It shows the two rocks are at the same height at 8.6 meters (if they're launched at the same time).
... f(x) = g(x)
... -4.9x^2 +17 = -4.9x^2 +13x
... 17 = 13x . . . . . add 4.9x^2
... 17/13 = x . . . . time when rocks meet
... f(17/13) = -4.9(17/13)^2 +17 = -1416.1/169 +17 ≈ 8.62071
... f(17/13) ≈ 8.6 . . . . height at which rocks meet
Which equation is a quadratic model for the data set? Hint: Use a graphing calculator or a spreadsheet program.
Data table
Answer:
Equation for the quadratic model for the data set is;
[tex]y = 1.0774x^2-0.9393x+0.6905[/tex]
Step-by-step explanation:
A Quadratic regression is the process of finding the equation of the parabola that best fits the set of data.
An equation is in the form of: [tex]y=ax^2+bx+c[/tex] where a≠0.
You just enter the x-coordinates and y-coordinates in your graphing calculator and
then do a quadratic regression.
The equation of the parabola that best approximates the points is
:
[tex]y = 1.0774x^2-0.9393x+0.6905[/tex]
Now, plot the graph of the above equation as shown below in the figure.
Also you can see that the [tex]R^2[/tex] value for the above data is, 0.994
Light travels at a speed of 1.17 × 107 miles per minute. Pluto's average distance from the Sun is 3,670,000,000 miles. On average, how long does it take sunlight to reach Pluto? Enter your answer in scientific notation, and, if necessary, round your multiplier to the nearest hundredth.
Speed is the rate of change of distance over time.
It will take [tex]\mathbf{2.20 \times 10^{2}}[/tex] minutes to get to Pluto.
The given parameters are:
[tex]\mathbf{Speed = 1.17 \times 10^7 miles/mins}[/tex]
[tex]\mathbf{Distance = 3670000000 miles}[/tex]
Speed is calculated as:
[tex]\mathbf{Speed = \frac{Distance}{Time}}[/tex]
Make Time the subject
[tex]\mathbf{Time = \frac{Distance}{Speed}}[/tex]
Substitute values for Speed and Distance
[tex]\mathbf{Time = \frac{3670000000\ miles}{1.17 \times 10^7 miles/mins}}[/tex]
[tex]\mathbf{Time = \frac{3670000000\ mins}{1.17 \times 10^7 }}[/tex]
Rewrite as:
[tex]\mathbf{Time = \frac{3.67\times 10^9\ mins}{1.17 \times 10^7 }}[/tex]
Apply law of indices
[tex]\mathbf{Time = \frac{3.67\times 10^{9 - 7}\ mins}{1.17}}[/tex]
Divide
[tex]\mathbf{Time = 2.20 \times 10^{2}\ mins}[/tex]
Hence, it will take [tex]\mathbf{2.20 \times 10^{2}}[/tex] minutes to get to Pluto.
Read more about speed and rates at:
https://brainly.com/question/359790
I rent a gym for $150.00 for 30 students. Another time I rent the gym for $270.00 for 70 students. I need to find a fixed rate.
(y= mx+b)
Answer: y = 3x + 60
Step-by-step explanation:
Set up two equations and solve the system:
270 = 70x + b
- (150 = 30x + b)
120 = 40x
3 = x
Input "x" into one of the equations and solve for "b":
150 = 30x + b
150 = 30(3) + b
150 = 90 + b
60 = b
Equation: y = 3x + 60
This means that there is a flat fee of $60 plus a rate of $3 per student
The fixed rate of gym fee of $60 plus a rate of $3 per student.
The fixed-rate is;
[tex]\rm y=3x+60[/tex]
Given
I rent a gym for $150.00 for 30 students.
Another time I rent the gym for $270.00 for 70 students.
Linear function;A linear function is a function that forms a straight line in a graph.
Let x be the number of students and y be the total cost of renting the gym.
To find the fixed-rate let us write the equation of line representing the total cost of renting a gym for x students.
The equation representing a fixed rate is;
[tex]\rm y = mx+b[/tex]
I rent a gym for $150.00 for 30 students.
[tex]\rm 150 = 30x + b[/tex]
Another time I rent the gym for $270.00 for 70 students.
[tex]\rm 270 = 70x + b[/tex]
Subtracting both the equations;
[tex]\rm 150-270=30x+b-70x-b\\\\-120=-40x\\\\120=4x\\\\x=\dfrac{120}{4}\\\\x=3[/tex]
Substitute the value of x in equation 1
[tex]\rm 150 = 30x + b\\\\150=30(3)+b\\\\150=90+b\\\\b=150-90\\\\b=60[/tex]
Therefore,
The fixed-rate is;
[tex]\rm y=mx+b\\\\y=3x+60[/tex]
Hence, the fixed rate of gym fee of $60 plus a rate of $3 per student.'
To know more about linear function click the link given below.
https://brainly.com/question/371915
A total of 17,100 seats are still available for the next hockey game. If 62% of the tickets are sold, how many seats are in the arena? A. 7,100 seats B. 7,900 seats C. 45,000 seats D. 27,900 seats
Answer:
We have
seats x ( 62 / 100 ) = (seats - 17,100);
seats x 62 = 100 x (seats - 17,100);
seats x 62 = seats x 100 - 1710000;
1,710,000 = seats x 38;
seats = 1,710,000 ÷ 38;
seats = 45,000;
The correct answer is c. 45,000 seats;
Step-by-step explanation:
45, 000 A for plato users
Step-by-step explanation:
Trust me im Master chief
PLEASE HELP ASAP!!! CORRECT ANSWERS ONLY PLEASE!!
Simplify.
Answer:
(B): (x - 2)/(x + 1)
Step-by-step explanation:
The numerator is x^2 + 5x - 14. That is equal to (x - 2)(x + 7).
The denominator is x^2 + 8x + 7. That is equal to (x + 1)(x + 7).
You can then eliminate (x+7) to get (x - 2)/(x + 1).
Answer: B
Step-by-step explanation:
[tex]\dfrac{x^{2}+5x-14}{x^{2}+8x+7}[/tex]
[tex]=\dfrac{(x+7)(x-2)}{(x+7)(x+1)}[/tex]
[tex]=\dfrac{(x-2)}{(x+1)}[/tex]
please help me ill give brainliest
Answer:
The answer would be remove two negative tiles.
Step-by-step explanation:
-5-(-2) becomes -5+2, and since the latter aren't of the same sign, you'd subtract two negative tiles so that it gives you the answer, which would be -3.
How to:
-5-(-2)
-5+2
= -3
Answer:
B) Remove 2 negative tiles
Step-by-step explanation:
-5 - (-2)
-5 + 2 [-(-2) = +2]
= -3
Remove two negative tiles
Answer: Remove 2 negative tiles
What is the vertex and axis of symmetry for y=4x^2-12x+9?
Answer:
axis of symmetry x=3/2
vertex (3/2, 0)
Step-by-step explanation:
to find the axis of symmetry we use h = -b/2a
where ax^2 + bx+c
h = -(-12)/2(4)
h= 12/8
h = 3/2
the axis of symmetry is x = 3/2
the x coordinate of the vertex is h x=3/2
to find k, the y coordinate of the vertex, substitute x=3/2 into the equation
y=4x^2-12x+9
y=4(3/2) ^2-12(3/2)+9
= 4 (9/4) - 6*3 +9
= 9-18+9
= 0
the vertex (3/2, 0)
A graph is translated according to the following rule. Describe the translation.
(x, y) → (x, y – 3)
The graph is translated three units to the right.
The graph is translated three units to the left.
The graph is translated three units down.
The graph is translated three units up.
Answer:
The graph is translated three units down.
Step-by-step explanation:
We know that, a 'Translation' is an transformation where the figure or graph is shifted in any direction.
According to our question (x,y) becomes (x, y-3) , this means that the graph value of 'x' co-ordinate remains same and the value of 'y' co-ordinate is decreased by 3 units.
So, the graph is shifted three units downwards i.e. it is translated three units down.
Sinea wants to spend money using the same ratios as on her last trip to the car nivel. If she spends $26 on games,how much will she spend on souvenirs? CHART Snacks Games Souvenirs Sinea $5 $8 $12 Ren. $10 $8 $20
Answer:
A. Sinea spends $26 on games, she wants to keep the same ratio, how much does she spend on souvenirs?
A- (snacks- 16.25) (games- 26) (souvenirs- 39)
B. Ren spends $5 on souvenirs, he wants to keep the same ratio, how much does he spend on snacks
B- (snacks- 2.5) (games- 2) (souvenirs- 5)
C. Both spend $40 on snacks, they want to keep their original ratio, who spends more on souvenirs?
C. Ratios
Sinea- (snacks- 40) (game- 64) (souvenirs- 96)
Ren- (snacks- 40) (game- 32) (souvenirs- 80)
Please answer quickly, more might be coming soon. 50 Points!
Answer:
2) ∠SDH and ∠SDT are right angles because SD ⊥ HT.
3) [tex]\bar{SH}\cong \bar{ST}[/tex] as it is given in the question.
4) [tex]\bar{SD}\cong \bar{SD}[/tex] is the reflexive property.
5) ΔSHD ≅ ΔSTD by RHS congruency.
Step-by-step explanation:
Given in the question:
[tex]\bar{SH}\cong \bar{ST}\\\bar{SD}\perp \bar{HT}[/tex]
In ΔSHD and ΔSTD
[tex]\bar{SH}\cong \bar{ST}[/tex] (Given)
[tex]\angle SDH\cong \angle SDT=90^o[/tex] (SD ⊥ HT)
[tex]\bar{SD}\cong \bar{SD}[/tex] (Common)
Therefore, [tex]\Delta SHD\cong \Delta STD[/tex] (By RHS rule)
Reflexive property of congruency is defined as the property in which something is equal to itself. Hence, the reflexive property of these two triangles is [tex]\bar{SD}\cong \bar{SD}[/tex]
Write an explicit formula for the sequence -13, -6, 1, 8, ...
a) an = -13n+7
b) an = -13+(n+7)
c) an = -13+7(n-1)
d) an = -13n+7
Answer:
c) an = -13+7(n-1)
Step-by-step explanation:
We can use the formula for arithmetic sequences
an =a1+d(n-1)
where a1 is the first term in the sequence
d is the common difference
and n is the term number
a1 is -13
d is found by taking the second term and subtracting the first term
d = -6--13
= -6+13
d=7
We are adding 7 each time
Substituting what we know,
an = -13 + 7(n-1)
The answer is:
c) [tex]a_{n}=-13+7(n-1)[/tex]