Question

7x - 5y = 22
7x - 9y = 6
What's y?

Answer 1

so you need to first cancel out x  so multiply -1 to one of the equations i'm gong to pick the second one so now it is 7x-5y=22 and -7x+9y=-6 then add so 4y=16 so y=4

Answer 2

You can do this by taking away the second equation from the first to get rid of the x terms so:

7x - 7x = 0
-5y - -9y = - 5y + 9y = 4y
22-6 = 16

So you are left with the equation:
4y = 16

Divide both sides by 4 to find y
y = 4