Solve 10x + 5 = 15
The solution of 10x + 5 = 15 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 5 from both sides:
- 3
Divide both sides by 10:
- 4
Check: put x = 1 back into the equation.
LaTeX source of the formulas on this page
\[ 10x + 5 = 15\ \Rightarrow\ x = 1 \]
\[ 10x + 5 = 15 \]
\[ 10x + 5 - 5 = 15 - 5 \ \Rightarrow\ 10x = 10 \]
\[ \frac{10x}{10} = \frac{10}{10} \ \Rightarrow\ x = 1 \]
\[ 10\cdot1 + 5 = 10 + 5 = 15 \checkmark \]Trying values of x in 10x + 5 = 15
| x | 10x + 5 | Equals 15? |
|---|---|---|
| -1 | -5 | no |
| 0 | 5 | no |
| 1 | 15 | yes |
| 2 | 25 | no |
| 3 | 35 | no |
Questions
What is x in 10x + 5 = 15?
The solution of 10x + 5 = 15 is x = 1.
How do you solve 10x + 5 = 15?
Subtract 5 from both sides to get 10x = 10, then divide both sides by 10 to get x = 1.
How do I check the answer?
Replace x by 1: 10(1) + 5 = 15, which is 15.