y=-(x+1)(x-5)

Solution for y=-(x+1)(x-5) equation:

Simplifying
y = -1(x + 1)(x + -5)

Reorder the terms:
y = -1(1 + x)(x + -5)

Reorder the terms:
y = -1(1 + x)(-5 + x)

Multiply (1 + x) * (-5 + x)
y = -1(1(-5 + x) + x(-5 + x))
y = -1((-5 * 1 + x * 1) + x(-5 + x))
y = -1((-5 + 1x) + x(-5 + x))
y = -1(-5 + 1x + (-5 * x + x * x))
y = -1(-5 + 1x + (-5x + x2))

Combine like terms: 1x + -5x = -4x
y = -1(-5 + -4x + x2)
y = (-5 * -1 + -4x * -1 + x2 * -1)
y = (5 + 4x + -1x2)

Solving
y = 5 + 4x + -1x2

Solving for variable 'y'.

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

Simplifying
y = 5 + 4x + -1x2