Solve 8x + 15 = 63
The solution of 8x + 15 = 63 is x = 6.
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 15 from both sides:
- 3
Divide both sides by 8:
- 4
Check: put x = 6 back into the equation.
LaTeX source of the formulas on this page
\[ 8x + 15 = 63\ \Rightarrow\ x = 6 \]
\[ 8x + 15 = 63 \]
\[ 8x + 15 - 15 = 63 - 15 \ \Rightarrow\ 8x = 48 \]
\[ \frac{8x}{8} = \frac{48}{8} \ \Rightarrow\ x = 6 \]
\[ 8\cdot6 + 15 = 48 + 15 = 63 \checkmark \]Trying values of x in 8x + 15 = 63
| x | 8x + 15 | Equals 63? |
|---|---|---|
| 4 | 47 | no |
| 5 | 55 | no |
| 6 | 63 | yes |
| 7 | 71 | no |
| 8 | 79 | no |
Questions
What is x in 8x + 15 = 63?
The solution of 8x + 15 = 63 is x = 6.
How do you solve 8x + 15 = 63?
Subtract 15 from both sides to get 8x = 48, then divide both sides by 8 to get x = 6.
How do I check the answer?
Replace x by 6: 8(6) + 15 = 63, which is 63.