Solve 7x ā 6 = 15
The solution of 7x ā 6 = 15 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 subtraction, then the multiplication.
- 2
Add 6 to both sides:
- 3
Divide both sides by 7:
- 4
Check: put x = 3 back into the equation.
LaTeX source of the formulas on this page
\[ 7x - 6 = 15\ \Rightarrow\ x = 3 \]
\[ 7x - 6 = 15 \]
\[ 7x - 6 + 6 = 15 + 6 \ \Rightarrow\ 7x = 21 \]
\[ \frac{7x}{7} = \frac{21}{7} \ \Rightarrow\ x = 3 \]
\[ 7\cdot3 - 6 = 21 - 6 = 15 \checkmark \]Trying values of x in 7x ā 6 = 15
| x | 7x ā 6 | Equals 15? |
|---|---|---|
| 1 | 1 | no |
| 2 | 8 | no |
| 3 | 15 | yes |
| 4 | 22 | no |
| 5 | 29 | no |
Questions
What is x in 7x ā 6 = 15?
The solution of 7x ā 6 = 15 is x = 3.
How do you solve 7x ā 6 = 15?
Add 6 to both sides to get 7x = 21, then divide both sides by 7 to get x = 3.
How do I check the answer?
Replace x by 3: 7(3) ā 6 = 15, which is 15.