Solve 2x + 13 = 43
The solution of 2x + 13 = 43 is x = 15.
How to work it out
- 1
The goal is to get x alone. Undo the operations in the opposite order: first the addition, then the multiplication.
- 2
Subtract 13 from both sides:
- 3
Divide both sides by 2:
- 4
Check: put x = 15 back into the equation.
LaTeX source of the formulas on this page
\[ 2x + 13 = 43\ \Rightarrow\ x = 15 \]
\[ 2x + 13 = 43 \]
\[ 2x + 13 - 13 = 43 - 13 \ \Rightarrow\ 2x = 30 \]
\[ \frac{2x}{2} = \frac{30}{2} \ \Rightarrow\ x = 15 \]
\[ 2\cdot15 + 13 = 30 + 13 = 43 \checkmark \]Trying values of x in 2x + 13 = 43
| x | 2x + 13 | Equals 43? |
|---|---|---|
| 13 | 39 | no |
| 14 | 41 | no |
| 15 | 43 | yes |
| 16 | 45 | no |
| 17 | 47 | no |
Questions
What is x in 2x + 13 = 43?
The solution of 2x + 13 = 43 is x = 15.
How do you solve 2x + 13 = 43?
Subtract 13 from both sides to get 2x = 30, then divide both sides by 2 to get x = 15.
How do I check the answer?
Replace x by 15: 2(15) + 13 = 43, which is 43.