(z-4)(-5)=0

Solution for (z-4)(-5)=0 equation:

Simplifying
(z + -4)(-5) = 0

Reorder the terms:
(-4 + z)(-5) = 0

Reorder the terms for easier multiplication:
-5(-4 + z) = 0
(-4 * -5 + z * -5) = 0
(20 + -5z) = 0

Solving
20 + -5z = 0

Solving for variable 'z'.

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

Add '-20' to each side of the equation.
20 + -20 + -5z = 0 + -20

Combine like terms: 20 + -20 = 0
0 + -5z = 0 + -20
-5z = 0 + -20

Combine like terms: 0 + -20 = -20
-5z = -20

Divide each side by '-5'.
z = 4

Simplifying
z = 4