(x+3)(x-4)=x^2-x+c

Solution for (x+3)(x-4)=x^2-x+c equation:

Simplifying
(x + 3)(x + -4) = x2 + -1x + c

Reorder the terms:
(3 + x)(x + -4) = x2 + -1x + c

Reorder the terms:
(3 + x)(-4 + x) = x2 + -1x + c

Multiply (3 + x) * (-4 + x)
(3(-4 + x) + x(-4 + x)) = x2 + -1x + c
((-4 * 3 + x * 3) + x(-4 + x)) = x2 + -1x + c
((-12 + 3x) + x(-4 + x)) = x2 + -1x + c
(-12 + 3x + (-4 * x + x * x)) = x2 + -1x + c
(-12 + 3x + (-4x + x2)) = x2 + -1x + c

Combine like terms: 3x + -4x = -1x
(-12 + -1x + x2) = x2 + -1x + c

Reorder the terms:
-12 + -1x + x2 = c + -1x + x2

Add 'x' to each side of the equation.
-12 + -1x + x + x2 = c + -1x + x + x2

Combine like terms: -1x + x = 0
-12 + 0 + x2 = c + -1x + x + x2
-12 + x2 = c + -1x + x + x2

Combine like terms: -1x + x = 0
-12 + x2 = c + 0 + x2
-12 + x2 = c + x2

Add '-1x2' to each side of the equation.
-12 + x2 + -1x2 = c + x2 + -1x2

Combine like terms: x2 + -1x2 = 0
-12 + 0 = c + x2 + -1x2
-12 = c + x2 + -1x2

Combine like terms: x2 + -1x2 = 0
-12 = c + 0
-12 = c

Solving
-12 = c

Solving for variable 'c'.

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

Add '-1c' to each side of the equation.
-12 + -1c = c + -1c

Combine like terms: c + -1c = 0
-12 + -1c = 0

Add '12' to each side of the equation.
-12 + 12 + -1c = 0 + 12

Combine like terms: -12 + 12 = 0
0 + -1c = 0 + 12
-1c = 0 + 12

Combine like terms: 0 + 12 = 12
-1c = 12

Divide each side by '-1'.
c = -12

Simplifying
c = -12