Solve 7x + 12 = 5
The solution of 7x + 12 = 5 is x = -1.
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 12 from both sides:
- 3
Divide both sides by 7:
- 4
Check: put x = -1 back into the equation.
LaTeX source of the formulas on this page
\[ 7x + 12 = 5\ \Rightarrow\ x = -1 \]
\[ 7x + 12 = 5 \]
\[ 7x + 12 - 12 = 5 - 12 \ \Rightarrow\ 7x = -7 \]
\[ \frac{7x}{7} = \frac{-7}{7} \ \Rightarrow\ x = -1 \]
\[ 7\cdot(-1) + 12 = -7 + 12 = 5 \checkmark \]Trying values of x in 7x + 12 = 5
| x | 7x + 12 | Equals 5? |
|---|---|---|
| -3 | -9 | no |
| -2 | -2 | no |
| -1 | 5 | yes |
| 0 | 12 | no |
| 1 | 19 | no |
Questions
What is x in 7x + 12 = 5?
The solution of 7x + 12 = 5 is x = -1.
How do you solve 7x + 12 = 5?
Subtract 12 from both sides to get 7x = -7, then divide both sides by 7 to get x = -1.
How do I check the answer?
Replace x by -1: 7(-1) + 12 = 5, which is 5.