Solve 10x + 1 = 31
The solution of 10x + 1 = 31 is x = 3.
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 1 from both sides:
- 3
Divide both sides by 10:
- 4
Check: put x = 3 back into the equation.
LaTeX source of the formulas on this page
\[ 10x + 1 = 31\ \Rightarrow\ x = 3 \]
\[ 10x + 1 = 31 \]
\[ 10x + 1 - 1 = 31 - 1 \ \Rightarrow\ 10x = 30 \]
\[ \frac{10x}{10} = \frac{30}{10} \ \Rightarrow\ x = 3 \]
\[ 10\cdot3 + 1 = 30 + 1 = 31 \checkmark \]Trying values of x in 10x + 1 = 31
| x | 10x + 1 | Equals 31? |
|---|---|---|
| 1 | 11 | no |
| 2 | 21 | no |
| 3 | 31 | yes |
| 4 | 41 | no |
| 5 | 51 | no |
Questions
What is x in 10x + 1 = 31?
The solution of 10x + 1 = 31 is x = 3.
How do you solve 10x + 1 = 31?
Subtract 1 from both sides to get 10x = 30, then divide both sides by 10 to get x = 3.
How do I check the answer?
Replace x by 3: 10(3) + 1 = 31, which is 31.