Solve 6x ā 15 = ā39
The solution of 6x ā 15 = ā39 is x = -4.
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 15 to both sides:
- 3
Divide both sides by 6:
- 4
Check: put x = -4 back into the equation.
LaTeX source of the formulas on this page
\[ 6x - 15 = -39\ \Rightarrow\ x = -4 \]
\[ 6x - 15 = -39 \]
\[ 6x - 15 + 15 = -39 + 15 \ \Rightarrow\ 6x = -24 \]
\[ \frac{6x}{6} = \frac{-24}{6} \ \Rightarrow\ x = -4 \]
\[ 6\cdot(-4) - 15 = -24 - 15 = -39 \checkmark \]Trying values of x in 6x ā 15 = ā39
| x | 6x ā 15 | Equals -39? |
|---|---|---|
| -6 | -51 | no |
| -5 | -45 | no |
| -4 | -39 | yes |
| -3 | -33 | no |
| -2 | -27 | no |
Questions
What is x in 6x ā 15 = ā39?
The solution of 6x ā 15 = ā39 is x = -4.
How do you solve 6x ā 15 = ā39?
Add 15 to both sides to get 6x = -24, then divide both sides by 6 to get x = -4.
How do I check the answer?
Replace x by -4: 6(-4) ā 15 = -39, which is -39.