Solve 4x ā 3 = ā15
The solution of 4x ā 3 = ā15 is x = -3.
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 3 to both sides:
- 3
Divide both sides by 4:
- 4
Check: put x = -3 back into the equation.
LaTeX source of the formulas on this page
\[ 4x - 3 = -15\ \Rightarrow\ x = -3 \]
\[ 4x - 3 = -15 \]
\[ 4x - 3 + 3 = -15 + 3 \ \Rightarrow\ 4x = -12 \]
\[ \frac{4x}{4} = \frac{-12}{4} \ \Rightarrow\ x = -3 \]
\[ 4\cdot(-3) - 3 = -12 - 3 = -15 \checkmark \]Trying values of x in 4x ā 3 = ā15
| x | 4x ā 3 | Equals -15? |
|---|---|---|
| -5 | -23 | no |
| -4 | -19 | no |
| -3 | -15 | yes |
| -2 | -11 | no |
| -1 | -7 | no |
Questions
What is x in 4x ā 3 = ā15?
The solution of 4x ā 3 = ā15 is x = -3.
How do you solve 4x ā 3 = ā15?
Add 3 to both sides to get 4x = -12, then divide both sides by 4 to get x = -3.
How do I check the answer?
Replace x by -3: 4(-3) ā 3 = -15, which is -15.