(1+x)(4-5)=

Solution for (1+x)(4-5)= equation:

Simplifying
(1 + x)(4 + -5) = 0

Combine like terms: 4 + -5 = -1
(1 + x)(-1) = 0

Reorder the terms for easier multiplication:
-1(1 + x) = 0
(1 * -1 + x * -1) = 0
(-1 + -1x) = 0

Solving
-1 + -1x = 0

Solving for variable 'x'.

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

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

Combine like terms: -1 + 1 = 0
0 + -1x = 0 + 1
-1x = 0 + 1

Combine like terms: 0 + 1 = 1
-1x = 1

Divide each side by '-1'.
x = -1

Simplifying
x = -1