f(x)=3(x+9)(x-16)

Solution for f(x)=3(x+9)(x-16) equation:

Simplifying
f(x) = 3(x + 9)(x + -16)

Multiply f * x
fx = 3(x + 9)(x + -16)

Reorder the terms:
fx = 3(9 + x)(x + -16)

Reorder the terms:
fx = 3(9 + x)(-16 + x)

Multiply (9 + x) * (-16 + x)
fx = 3(9(-16 + x) + x(-16 + x))
fx = 3((-16 * 9 + x * 9) + x(-16 + x))
fx = 3((-144 + 9x) + x(-16 + x))
fx = 3(-144 + 9x + (-16 * x + x * x))
fx = 3(-144 + 9x + (-16x + x2))

Combine like terms: 9x + -16x = -7x
fx = 3(-144 + -7x + x2)
fx = (-144 * 3 + -7x * 3 + x2 * 3)
fx = (-432 + -21x + 3x2)

Solving
fx = -432 + -21x + 3x2

Solving for variable 'f'.

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

Divide each side by 'x'.
f = -432x-1 + -21 + 3x

Simplifying
f = -432x-1 + -21 + 3x

Reorder the terms:
f = -21 + -432x-1 + 3x