Solve 12x ā 12 = ā120
The solution of 12x ā 12 = ā120 is x = -9.
How to work it out
- 1
The goal is to get x alone. Undo the operations in the opposite order: first the subtraction, then the multiplication.
- 2
Add 12 to both sides:
- 3
Divide both sides by 12:
- 4
Check: put x = -9 back into the equation.
LaTeX source of the formulas on this page
\[ 12x - 12 = -120\ \Rightarrow\ x = -9 \]
\[ 12x - 12 = -120 \]
\[ 12x - 12 + 12 = -120 + 12 \ \Rightarrow\ 12x = -108 \]
\[ \frac{12x}{12} = \frac{-108}{12} \ \Rightarrow\ x = -9 \]
\[ 12\cdot(-9) - 12 = -108 - 12 = -120 \checkmark \]Trying values of x in 12x ā 12 = ā120
| x | 12x ā 12 | Equals -120? |
|---|---|---|
| -11 | -144 | no |
| -10 | -132 | no |
| -9 | -120 | yes |
| -8 | -108 | no |
| -7 | -96 | no |
Questions
What is x in 12x ā 12 = ā120?
The solution of 12x ā 12 = ā120 is x = -9.
How do you solve 12x ā 12 = ā120?
Add 12 to both sides to get 12x = -108, then divide both sides by 12 to get x = -9.
How do I check the answer?
Replace x by -9: 12(-9) ā 12 = -120, which is -120.