100-(y+15)=42

Solution for 100-(y+15)=42 equation:

Simplifying
100 + -1(y + 15) = 42

Reorder the terms:
100 + -1(15 + y) = 42
100 + (15 * -1 + y * -1) = 42
100 + (-15 + -1y) = 42

Combine like terms: 100 + -15 = 85
85 + -1y = 42

Solving
85 + -1y = 42

Solving for variable 'y'.

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

Add '-85' to each side of the equation.
85 + -85 + -1y = 42 + -85

Combine like terms: 85 + -85 = 0
0 + -1y = 42 + -85
-1y = 42 + -85

Combine like terms: 42 + -85 = -43
-1y = -43

Divide each side by '-1'.
y = 43

Simplifying
y = 43