Solve 12x ā 12 = ā72
The solution of 12x ā 12 = ā72 is x = -5.
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 = -5 back into the equation.
LaTeX source of the formulas on this page
\[ 12x - 12 = -72\ \Rightarrow\ x = -5 \]
\[ 12x - 12 = -72 \]
\[ 12x - 12 + 12 = -72 + 12 \ \Rightarrow\ 12x = -60 \]
\[ \frac{12x}{12} = \frac{-60}{12} \ \Rightarrow\ x = -5 \]
\[ 12\cdot(-5) - 12 = -60 - 12 = -72 \checkmark \]Trying values of x in 12x ā 12 = ā72
| x | 12x ā 12 | Equals -72? |
|---|---|---|
| -7 | -96 | no |
| -6 | -84 | no |
| -5 | -72 | yes |
| -4 | -60 | no |
| -3 | -48 | no |
Questions
What is x in 12x ā 12 = ā72?
The solution of 12x ā 12 = ā72 is x = -5.
How do you solve 12x ā 12 = ā72?
Add 12 to both sides to get 12x = -60, then divide both sides by 12 to get x = -5.
How do I check the answer?
Replace x by -5: 12(-5) ā 12 = -72, which is -72.