Hello there! 
Well, let me solve the system of equation first then I will graph it :) 
y = 2x - 7 
y = -2x + 1 
We need to solve y = 2x - 7 for y 
Start by substituting 2x - 7 for y in y = -2x + 1: 
y = -2x + 1 
2x - 7 = -2x + 1 
Add 2x on both sides 
2x - 7 + 2x = -2x + 1 + 2x 
4x - 7 = 1 
Then add 7 on both sides 
4x - 7 + 7 = 1 + 7 
4x = 8 
Divide both sides by 4
4x/4 = 8/4
x = 2 
We found x! We can use that number to find the value for y 
We can do that by substitute 2 for x in y = 2x - 7 
y = 2x - 7 
y = 2(2) - 7 
y = 4 - 7 
y = -3 
Now how do we graph these answers? 
Well, we have x = 2 and y = -3 all we have to do is go on the graph and find where these numbers are located. 
I used a graphing online....check the attachment below!
As always it is my pleasure to help students like you. Let me know if you have any questions.