Solve 9x + 1 = ā89
The solution of 9x + 1 = ā89 is x = -10.
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 1 from both sides:
- 3
Divide both sides by 9:
- 4
Check: put x = -10 back into the equation.
LaTeX source of the formulas on this page
\[ 9x + 1 = -89\ \Rightarrow\ x = -10 \]
\[ 9x + 1 = -89 \]
\[ 9x + 1 - 1 = -89 - 1 \ \Rightarrow\ 9x = -90 \]
\[ \frac{9x}{9} = \frac{-90}{9} \ \Rightarrow\ x = -10 \]
\[ 9\cdot(-10) + 1 = -90 + 1 = -89 \checkmark \]Trying values of x in 9x + 1 = ā89
| x | 9x + 1 | Equals -89? |
|---|---|---|
| -12 | -107 | no |
| -11 | -98 | no |
| -10 | -89 | yes |
| -9 | -80 | no |
| -8 | -71 | no |
Questions
What is x in 9x + 1 = ā89?
The solution of 9x + 1 = ā89 is x = -10.
How do you solve 9x + 1 = ā89?
Subtract 1 from both sides to get 9x = -90, then divide both sides by 9 to get x = -10.
How do I check the answer?
Replace x by -10: 9(-10) + 1 = -89, which is -89.