39*39-36*36=y*y

Solution for 39*39-36*36=y*y equation:

Simplifying
39 * 39 + -36 * 36 = y * y

Multiply 39 * 39
1521 + -36 * 36 = y * y

Multiply -36 * 36
1521 + -1296 = y * y

Combine like terms: 1521 + -1296 = 225
225 = y * y

Multiply y * y
225 = y2

Solving
225 = y2

Solving for variable 'y'.

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

Add '-1y2' to each side of the equation.
225 + -1y2 = y2 + -1y2

Combine like terms: y2 + -1y2 = 0
225 + -1y2 = 0

Add '-225' to each side of the equation.
225 + -225 + -1y2 = 0 + -225

Combine like terms: 225 + -225 = 0
0 + -1y2 = 0 + -225
-1y2 = 0 + -225

Combine like terms: 0 + -225 = -225
-1y2 = -225

Divide each side by '-1'.
y2 = 225

Simplifying
y2 = 225

Take the square root of each side:
y = {-15, 15}