Question

4*y - 70 = 12*y + 2

Answer 1

 4y-70=12y+2
-4y      -4y
     -70 = 8y+2
     -2           -2
$\frac{-72}{8} =\frac{8y}{8}$

Answer 2

Refer to picture:
You need to get the variable to one side of the equation so you need to subtract the coefficient(the variable and it's number) on both sides. Now you need the constants(the stand alone numbers) to be on one side so subtract from both sides again. You now should have -72=8y if you did the subtraction like I did(you don't have to do the subtraction my way, it would work the other way too). Now simply isolate the variable by dividing by 8 and you have -9 as your answer.