Solve 7x ā 1 = 69
The solution of 7x ā 1 = 69 is x = 10.
How to work it out
- 1
The goal is to get x alone. Undo the operations in the opposite order: first the subtraction, then the multiplication.
- 2
Add 1 to both sides:
- 3
Divide both sides by 7:
- 4
Check: put x = 10 back into the equation.
LaTeX source of the formulas on this page
\[ 7x - 1 = 69\ \Rightarrow\ x = 10 \]
\[ 7x - 1 = 69 \]
\[ 7x - 1 + 1 = 69 + 1 \ \Rightarrow\ 7x = 70 \]
\[ \frac{7x}{7} = \frac{70}{7} \ \Rightarrow\ x = 10 \]
\[ 7\cdot10 - 1 = 70 - 1 = 69 \checkmark \]Trying values of x in 7x ā 1 = 69
| x | 7x ā 1 | Equals 69? |
|---|---|---|
| 8 | 55 | no |
| 9 | 62 | no |
| 10 | 69 | yes |
| 11 | 76 | no |
| 12 | 83 | no |
Questions
What is x in 7x ā 1 = 69?
The solution of 7x ā 1 = 69 is x = 10.
How do you solve 7x ā 1 = 69?
Add 1 to both sides to get 7x = 70, then divide both sides by 7 to get x = 10.
How do I check the answer?
Replace x by 10: 7(10) ā 1 = 69, which is 69.