Simplify 2y + 7 - 5y to -3y + 7
-17 = -3y + 7
Subtract 7 from both sides
-17 - 7 = -3y
Simplify -17 - 7 to -24
-24 = -3y
Divide both sides by -3
-24/-3 = y
Two negatives make a positive
24/3 = y
Simplify 24/3 to 8
8 = y
Switch sides
y = 8
