Solve 5x + 7 = 12
The solution of 5x + 7 = 12 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 7 from both sides:
- 3
Divide both sides by 5:
- 4
Check: put x = 1 back into the equation.
LaTeX source of the formulas on this page
\[ 5x + 7 = 12\ \Rightarrow\ x = 1 \]
\[ 5x + 7 = 12 \]
\[ 5x + 7 - 7 = 12 - 7 \ \Rightarrow\ 5x = 5 \]
\[ \frac{5x}{5} = \frac{5}{5} \ \Rightarrow\ x = 1 \]
\[ 5\cdot1 + 7 = 5 + 7 = 12 \checkmark \]Trying values of x in 5x + 7 = 12
| x | 5x + 7 | Equals 12? |
|---|---|---|
| -1 | 2 | no |
| 0 | 7 | no |
| 1 | 12 | yes |
| 2 | 17 | no |
| 3 | 22 | no |
Questions
What is x in 5x + 7 = 12?
The solution of 5x + 7 = 12 is x = 1.
How do you solve 5x + 7 = 12?
Subtract 7 from both sides to get 5x = 5, then divide both sides by 5 to get x = 1.
How do I check the answer?
Replace x by 1: 5(1) + 7 = 12, which is 12.