Solve 8x + 8 = 72
The solution of 8x + 8 = 72 is x = 8.
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 8 from both sides:
- 3
Divide both sides by 8:
- 4
Check: put x = 8 back into the equation.
LaTeX source of the formulas on this page
\[ 8x + 8 = 72\ \Rightarrow\ x = 8 \]
\[ 8x + 8 = 72 \]
\[ 8x + 8 - 8 = 72 - 8 \ \Rightarrow\ 8x = 64 \]
\[ \frac{8x}{8} = \frac{64}{8} \ \Rightarrow\ x = 8 \]
\[ 8\cdot8 + 8 = 64 + 8 = 72 \checkmark \]Trying values of x in 8x + 8 = 72
| x | 8x + 8 | Equals 72? |
|---|---|---|
| 6 | 56 | no |
| 7 | 64 | no |
| 8 | 72 | yes |
| 9 | 80 | no |
| 10 | 88 | no |
Questions
What is x in 8x + 8 = 72?
The solution of 8x + 8 = 72 is x = 8.
How do you solve 8x + 8 = 72?
Subtract 8 from both sides to get 8x = 64, then divide both sides by 8 to get x = 8.
How do I check the answer?
Replace x by 8: 8(8) + 8 = 72, which is 72.