Solve 8x ā 5 = ā61
The solution of 8x ā 5 = ā61 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 5 to both sides:
- 3
Divide both sides by 8:
- 4
Check: put x = -7 back into the equation.
LaTeX source of the formulas on this page
\[ 8x - 5 = -61\ \Rightarrow\ x = -7 \]
\[ 8x - 5 = -61 \]
\[ 8x - 5 + 5 = -61 + 5 \ \Rightarrow\ 8x = -56 \]
\[ \frac{8x}{8} = \frac{-56}{8} \ \Rightarrow\ x = -7 \]
\[ 8\cdot(-7) - 5 = -56 - 5 = -61 \checkmark \]Trying values of x in 8x ā 5 = ā61
| x | 8x ā 5 | Equals -61? |
|---|---|---|
| -9 | -77 | no |
| -8 | -69 | no |
| -7 | -61 | yes |
| -6 | -53 | no |
| -5 | -45 | no |
Questions
What is x in 8x ā 5 = ā61?
The solution of 8x ā 5 = ā61 is x = -7.
How do you solve 8x ā 5 = ā61?
Add 5 to both sides to get 8x = -56, then divide both sides by 8 to get x = -7.
How do I check the answer?
Replace x by -7: 8(-7) ā 5 = -61, which is -61.