Solve 7x + 9 = ā54
The solution of 7x + 9 = ā54 is x = -9.
How to work it out
- 1
The goal is to get x alone. Undo the operations in the opposite order: first the addition, then the multiplication.
- 2
Subtract 9 from both sides:
- 3
Divide both sides by 7:
- 4
Check: put x = -9 back into the equation.
LaTeX source of the formulas on this page
\[ 7x + 9 = -54\ \Rightarrow\ x = -9 \]
\[ 7x + 9 = -54 \]
\[ 7x + 9 - 9 = -54 - 9 \ \Rightarrow\ 7x = -63 \]
\[ \frac{7x}{7} = \frac{-63}{7} \ \Rightarrow\ x = -9 \]
\[ 7\cdot(-9) + 9 = -63 + 9 = -54 \checkmark \]Trying values of x in 7x + 9 = ā54
| x | 7x + 9 | Equals -54? |
|---|---|---|
| -11 | -68 | no |
| -10 | -61 | no |
| -9 | -54 | yes |
| -8 | -47 | no |
| -7 | -40 | no |
Questions
What is x in 7x + 9 = ā54?
The solution of 7x + 9 = ā54 is x = -9.
How do you solve 7x + 9 = ā54?
Subtract 9 from both sides to get 7x = -63, then divide both sides by 7 to get x = -9.
How do I check the answer?
Replace x by -9: 7(-9) + 9 = -54, which is -54.