SOLUTION: My seventh grade class just started on a unit within functions. Examples of what we are working on show up here: https://classroom.google.com/c/NDEyMDQ4MTkxNTda/p/NTAzNDMwMjg1MjZa

Algebra ->  Functions -> SOLUTION: My seventh grade class just started on a unit within functions. Examples of what we are working on show up here: https://classroom.google.com/c/NDEyMDQ4MTkxNTda/p/NTAzNDMwMjg1MjZa      Log On


   

Question 1151725: My seventh grade class just started on a unit within functions. Examples of what we are working on show up here:
https://classroom.google.com/c/NDEyMDQ4MTkxNTda/p/NTAzNDMwMjg1MjZa/details
Thing is, I don't know how to solve a problem that I've tried to solve by looking up YouTube tutorials. Please explain how to solve an equation for the following below:
x|y
2|-6
3|1
4|8
5|15
6|22
8|36
I came up with y = 7x + (-13) after countless YouTube tutorials but they all don't make sense to me. Please explain to me how to do this.
Found 2 solutions by ankor@dixie-net.com, ikleyn:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
x|y
2|-6
3|1
4|8
5|15
6|22
8|36
From the table assign the values as follows
x1=2, y1=-6
x2=8, y2=36
:
Find the slope using m=%28%28y2-y1%29%29%2F%28%28x2-x1%29%29
m=%28%2836-%28-6%29%29%29%2F%28%288-2%29%29 = 42%2F6 = 7
m=7
Using the point/slope form y - y1 = m(x - x1)
y -(-6) = 7(x - 2)
y + 6 = 7x - 14
y = 7x - 14 - 6
y = 7x - 20 is the equation
:
check this using the x value in the table and see if y = the given value
x=5 for example
y = 7(5) - 20
y = 35 - 20
y = 15
:
you can do this for all values in the table, it should make sense to you then

Answer by ikleyn(52790) About Me  (Show Source):
You can put this solution on YOUR website!
.

ANSWER.  y = 7x - 20.



Explanation


x = 2, 3, 4, . . . , 8  are consecutive integer numbers from 2 to 8 inclusive.


y increases by 7 every time as x increases by 1.


So you write  y = 7x + c     (1)    (linear function with the slope of 7).


The constant "c" is unknown now.


To find it, you substitute x = 2 to the right side of (1), and substitute y= -14 to the left side of (1).

In this way, you get  c = -20.

That's all.

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