Solve 12x + 7 = ā89
The solution of 12x + 7 = ā89 is x = -8.
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 7 from both sides:
- 3
Divide both sides by 12:
- 4
Check: put x = -8 back into the equation.
LaTeX source of the formulas on this page
\[ 12x + 7 = -89\ \Rightarrow\ x = -8 \]
\[ 12x + 7 = -89 \]
\[ 12x + 7 - 7 = -89 - 7 \ \Rightarrow\ 12x = -96 \]
\[ \frac{12x}{12} = \frac{-96}{12} \ \Rightarrow\ x = -8 \]
\[ 12\cdot(-8) + 7 = -96 + 7 = -89 \checkmark \]Trying values of x in 12x + 7 = ā89
| x | 12x + 7 | Equals -89? |
|---|---|---|
| -10 | -113 | no |
| -9 | -101 | no |
| -8 | -89 | yes |
| -7 | -77 | no |
| -6 | -65 | no |
Questions
What is x in 12x + 7 = ā89?
The solution of 12x + 7 = ā89 is x = -8.
How do you solve 12x + 7 = ā89?
Subtract 7 from both sides to get 12x = -96, then divide both sides by 12 to get x = -8.
How do I check the answer?
Replace x by -8: 12(-8) + 7 = -89, which is -89.