Solve 8x ā 13 = 131
The solution of 8x ā 13 = 131 is x = 18.
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 13 to both sides:
- 3
Divide both sides by 8:
- 4
Check: put x = 18 back into the equation.
LaTeX source of the formulas on this page
\[ 8x - 13 = 131\ \Rightarrow\ x = 18 \]
\[ 8x - 13 = 131 \]
\[ 8x - 13 + 13 = 131 + 13 \ \Rightarrow\ 8x = 144 \]
\[ \frac{8x}{8} = \frac{144}{8} \ \Rightarrow\ x = 18 \]
\[ 8\cdot18 - 13 = 144 - 13 = 131 \checkmark \]Trying values of x in 8x ā 13 = 131
| x | 8x ā 13 | Equals 131? |
|---|---|---|
| 16 | 115 | no |
| 17 | 123 | no |
| 18 | 131 | yes |
| 19 | 139 | no |
| 20 | 147 | no |
Questions
What is x in 8x ā 13 = 131?
The solution of 8x ā 13 = 131 is x = 18.
How do you solve 8x ā 13 = 131?
Add 13 to both sides to get 8x = 144, then divide both sides by 8 to get x = 18.
How do I check the answer?
Replace x by 18: 8(18) ā 13 = 131, which is 131.