how can i solve this[[-7x+2y=-5 10x-2y=6]] using linear combinations?

Question

i really dont ge this method

Answer 1

Step 1: Take your 2 equations and multiply them by a factor so that you can add them together and cancel out one of the variables. In this case, you don't need to multiply them at all:
-7x+2y=-5
10x-2y=6

Add them up:
10x - 2y + -7x + 2y = -5 + 6

Simplify:
3x = 1
x = 1/3 (solution!)

Substitute the answer for x into one of the equations:
-7x + 2y= -5
-7(1/3) + 2y = -5
-7/3 + 2y = -5
2y = -8/3
y = -4/3 (solution!)

Substitute both answers into the other equation to check:
10x - 2y = 6
10(1/3) - 2(-4/3) = 6
10/3 + 8/3 = 6
18/3 = 6
6 = 6 (check!)

Answer 2

Simplify: (5/2y)³