y=1(1-0.75)(y-100)

Solution for y=1(1-0.75)(y-100) equation:

Simplifying
y = 1(1 + -0.75)(y + -100)

Combine like terms: 1 + -0.75 = 0.25
y = 1(0.25)(y + -100)

Reorder the terms:
y = 1 * 0.25(-100 + y)

Multiply 1 * 0.25
y = 0.25(-100 + y)
y = (-100 * 0.25 + y * 0.25)
y = (-25 + 0.25y)

Solving
y = -25 + 0.25y

Solving for variable 'y'.

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

Add '-0.25y' to each side of the equation.
y + -0.25y = -25 + 0.25y + -0.25y

Combine like terms: y + -0.25y = 0.75y
0.75y = -25 + 0.25y + -0.25y

Combine like terms: 0.25y + -0.25y = 0.00
0.75y = -25 + 0.00
0.75y = -25

Divide each side by '0.75'.
y = -33.33333333

Simplifying
y = -33.33333333