Solve 7x ā 9 = ā2
The solution of 7x ā 9 = ā2 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 subtraction, then the multiplication.
- 2
Add 9 to both sides:
- 3
Divide both sides by 7:
- 4
Check: put x = 1 back into the equation.
LaTeX source of the formulas on this page
\[ 7x - 9 = -2\ \Rightarrow\ x = 1 \]
\[ 7x - 9 = -2 \]
\[ 7x - 9 + 9 = -2 + 9 \ \Rightarrow\ 7x = 7 \]
\[ \frac{7x}{7} = \frac{7}{7} \ \Rightarrow\ x = 1 \]
\[ 7\cdot1 - 9 = 7 - 9 = -2 \checkmark \]Trying values of x in 7x ā 9 = ā2
| x | 7x ā 9 | Equals -2? |
|---|---|---|
| -1 | -16 | no |
| 0 | -9 | no |
| 1 | -2 | yes |
| 2 | 5 | no |
| 3 | 12 | no |
Questions
What is x in 7x ā 9 = ā2?
The solution of 7x ā 9 = ā2 is x = 1.
How do you solve 7x ā 9 = ā2?
Add 9 to both sides to get 7x = 7, then divide both sides by 7 to get x = 1.
How do I check the answer?
Replace x by 1: 7(1) ā 9 = -2, which is -2.