Solve 5x ā 8 = ā43
The solution of 5x ā 8 = ā43 is x = -7.
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 8 to both sides:
- 3
Divide both sides by 5:
- 4
Check: put x = -7 back into the equation.
LaTeX source of the formulas on this page
\[ 5x - 8 = -43\ \Rightarrow\ x = -7 \]
\[ 5x - 8 = -43 \]
\[ 5x - 8 + 8 = -43 + 8 \ \Rightarrow\ 5x = -35 \]
\[ \frac{5x}{5} = \frac{-35}{5} \ \Rightarrow\ x = -7 \]
\[ 5\cdot(-7) - 8 = -35 - 8 = -43 \checkmark \]Trying values of x in 5x ā 8 = ā43
| x | 5x ā 8 | Equals -43? |
|---|---|---|
| -9 | -53 | no |
| -8 | -48 | no |
| -7 | -43 | yes |
| -6 | -38 | no |
| -5 | -33 | no |
Questions
What is x in 5x ā 8 = ā43?
The solution of 5x ā 8 = ā43 is x = -7.
How do you solve 5x ā 8 = ā43?
Add 8 to both sides to get 5x = -35, then divide both sides by 5 to get x = -7.
How do I check the answer?
Replace x by -7: 5(-7) ā 8 = -43, which is -43.