Solve 10x + 5 = 125
The solution of 10x + 5 = 125 is x = 12.
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 5 from both sides:
- 3
Divide both sides by 10:
- 4
Check: put x = 12 back into the equation.
LaTeX source of the formulas on this page
\[ 10x + 5 = 125\ \Rightarrow\ x = 12 \]
\[ 10x + 5 = 125 \]
\[ 10x + 5 - 5 = 125 - 5 \ \Rightarrow\ 10x = 120 \]
\[ \frac{10x}{10} = \frac{120}{10} \ \Rightarrow\ x = 12 \]
\[ 10\cdot12 + 5 = 120 + 5 = 125 \checkmark \]Trying values of x in 10x + 5 = 125
| x | 10x + 5 | Equals 125? |
|---|---|---|
| 10 | 105 | no |
| 11 | 115 | no |
| 12 | 125 | yes |
| 13 | 135 | no |
| 14 | 145 | no |
Questions
What is x in 10x + 5 = 125?
The solution of 10x + 5 = 125 is x = 12.
How do you solve 10x + 5 = 125?
Subtract 5 from both sides to get 10x = 120, then divide both sides by 10 to get x = 12.
How do I check the answer?
Replace x by 12: 10(12) + 5 = 125, which is 125.