15+(2-20)=y

Solution for 15+(2-20)=y equation:

Simplifying
15 + (2 + -20) = y

Combine like terms: 2 + -20 = -18
15 + (-18) = y
15 + -18 = y

Combine like terms: 15 + -18 = -3
-3 = y

Solving
-3 = y

Solving for variable 'y'.

Move all terms containing y to the left, all other terms to the right.

Add '-1y' to each side of the equation.
-3 + -1y = y + -1y

Combine like terms: y + -1y = 0
-3 + -1y = 0

Add '3' to each side of the equation.
-3 + 3 + -1y = 0 + 3

Combine like terms: -3 + 3 = 0
0 + -1y = 0 + 3
-1y = 0 + 3

Combine like terms: 0 + 3 = 3
-1y = 3

Divide each side by '-1'.
y = -3

Simplifying
y = -3