4 (x + 9) = 20 idk math

Mathematics · Middle School · Tue Nov 03 2020

Answered on

Given the numerical expression:

4(x + 9) = 20

Solution:
In order to simplify the numerical expression, distribute first 4 on each value inside the parenthesis.

4(x + 9) = 20

4x + 36 = 20

Transpose 20 on the other side of the equation. Note that when transposing a number, the sign changes.

4x + 36 - 20 = 0

Simplified answer: 4x + 16

In order to find the value of x, transpose 16 on the other side of the equation, and divide both sides by 4, to cancel out 4x.

4x + 16

4x = -16

x = -4

The value of x is -4.