Solve 12x + 4 = ā20
The solution of 12x + 4 = ā20 is x = -2.
How to work it out
- 1
The goal is to get x alone. Undo the operations in the opposite order: first the addition, then the multiplication.
- 2
Subtract 4 from both sides:
- 3
Divide both sides by 12:
- 4
Check: put x = -2 back into the equation.
LaTeX source of the formulas on this page
\[ 12x + 4 = -20\ \Rightarrow\ x = -2 \]
\[ 12x + 4 = -20 \]
\[ 12x + 4 - 4 = -20 - 4 \ \Rightarrow\ 12x = -24 \]
\[ \frac{12x}{12} = \frac{-24}{12} \ \Rightarrow\ x = -2 \]
\[ 12\cdot(-2) + 4 = -24 + 4 = -20 \checkmark \]Trying values of x in 12x + 4 = ā20
| x | 12x + 4 | Equals -20? |
|---|---|---|
| -4 | -44 | no |
| -3 | -32 | no |
| -2 | -20 | yes |
| -1 | -8 | no |
| 0 | 4 | no |
Questions
What is x in 12x + 4 = ā20?
The solution of 12x + 4 = ā20 is x = -2.
How do you solve 12x + 4 = ā20?
Subtract 4 from both sides to get 12x = -24, then divide both sides by 12 to get x = -2.
How do I check the answer?
Replace x by -2: 12(-2) + 4 = -20, which is -20.