Solve 9x ā 3 = ā75
The solution of 9x ā 3 = ā75 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 subtraction, then the multiplication.
- 2
Add 3 to both sides:
- 3
Divide both sides by 9:
- 4
Check: put x = -8 back into the equation.
LaTeX source of the formulas on this page
\[ 9x - 3 = -75\ \Rightarrow\ x = -8 \]
\[ 9x - 3 = -75 \]
\[ 9x - 3 + 3 = -75 + 3 \ \Rightarrow\ 9x = -72 \]
\[ \frac{9x}{9} = \frac{-72}{9} \ \Rightarrow\ x = -8 \]
\[ 9\cdot(-8) - 3 = -72 - 3 = -75 \checkmark \]Trying values of x in 9x ā 3 = ā75
| x | 9x ā 3 | Equals -75? |
|---|---|---|
| -10 | -93 | no |
| -9 | -84 | no |
| -8 | -75 | yes |
| -7 | -66 | no |
| -6 | -57 | no |
Questions
What is x in 9x ā 3 = ā75?
The solution of 9x ā 3 = ā75 is x = -8.
How do you solve 9x ā 3 = ā75?
Add 3 to both sides to get 9x = -72, then divide both sides by 9 to get x = -8.
How do I check the answer?
Replace x by -8: 9(-8) ā 3 = -75, which is -75.