Solve 9x ā 7 = ā25
The solution of 9x ā 7 = ā25 is x = -2.
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 7 to both sides:
- 3
Divide both sides by 9:
- 4
Check: put x = -2 back into the equation.
LaTeX source of the formulas on this page
\[ 9x - 7 = -25\ \Rightarrow\ x = -2 \]
\[ 9x - 7 = -25 \]
\[ 9x - 7 + 7 = -25 + 7 \ \Rightarrow\ 9x = -18 \]
\[ \frac{9x}{9} = \frac{-18}{9} \ \Rightarrow\ x = -2 \]
\[ 9\cdot(-2) - 7 = -18 - 7 = -25 \checkmark \]Trying values of x in 9x ā 7 = ā25
| x | 9x ā 7 | Equals -25? |
|---|---|---|
| -4 | -43 | no |
| -3 | -34 | no |
| -2 | -25 | yes |
| -1 | -16 | no |
| 0 | -7 | no |
Questions
What is x in 9x ā 7 = ā25?
The solution of 9x ā 7 = ā25 is x = -2.
How do you solve 9x ā 7 = ā25?
Add 7 to both sides to get 9x = -18, then divide both sides by 9 to get x = -2.
How do I check the answer?
Replace x by -2: 9(-2) ā 7 = -25, which is -25.