Solve 4x ā 10 = 42
The solution of 4x ā 10 = 42 is x = 13.
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 10 to both sides:
- 3
Divide both sides by 4:
- 4
Check: put x = 13 back into the equation.
LaTeX source of the formulas on this page
\[ 4x - 10 = 42\ \Rightarrow\ x = 13 \]
\[ 4x - 10 = 42 \]
\[ 4x - 10 + 10 = 42 + 10 \ \Rightarrow\ 4x = 52 \]
\[ \frac{4x}{4} = \frac{52}{4} \ \Rightarrow\ x = 13 \]
\[ 4\cdot13 - 10 = 52 - 10 = 42 \checkmark \]Trying values of x in 4x ā 10 = 42
| x | 4x ā 10 | Equals 42? |
|---|---|---|
| 11 | 34 | no |
| 12 | 38 | no |
| 13 | 42 | yes |
| 14 | 46 | no |
| 15 | 50 | no |
Questions
What is x in 4x ā 10 = 42?
The solution of 4x ā 10 = 42 is x = 13.
How do you solve 4x ā 10 = 42?
Add 10 to both sides to get 4x = 52, then divide both sides by 4 to get x = 13.
How do I check the answer?
Replace x by 13: 4(13) ā 10 = 42, which is 42.