Solve 2x + 13 = 51
The solution of 2x + 13 = 51 is x = 19.
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 = 19 back into the equation.
LaTeX source of the formulas on this page
\[ 2x + 13 = 51\ \Rightarrow\ x = 19 \]
\[ 2x + 13 = 51 \]
\[ 2x + 13 - 13 = 51 - 13 \ \Rightarrow\ 2x = 38 \]
\[ \frac{2x}{2} = \frac{38}{2} \ \Rightarrow\ x = 19 \]
\[ 2\cdot19 + 13 = 38 + 13 = 51 \checkmark \]Trying values of x in 2x + 13 = 51
| x | 2x + 13 | Equals 51? |
|---|---|---|
| 17 | 47 | no |
| 18 | 49 | no |
| 19 | 51 | yes |
| 20 | 53 | no |
| 21 | 55 | no |
Questions
What is x in 2x + 13 = 51?
The solution of 2x + 13 = 51 is x = 19.
How do you solve 2x + 13 = 51?
Subtract 13 from both sides to get 2x = 38, then divide both sides by 2 to get x = 19.
How do I check the answer?
Replace x by 19: 2(19) + 13 = 51, which is 51.