Solve 3x + 8 = 11
The solution of 3x + 8 = 11 is x = 1.
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 8 from both sides:
- 3
Divide both sides by 3:
- 4
Check: put x = 1 back into the equation.
LaTeX source of the formulas on this page
\[ 3x + 8 = 11\ \Rightarrow\ x = 1 \]
\[ 3x + 8 = 11 \]
\[ 3x + 8 - 8 = 11 - 8 \ \Rightarrow\ 3x = 3 \]
\[ \frac{3x}{3} = \frac{3}{3} \ \Rightarrow\ x = 1 \]
\[ 3\cdot1 + 8 = 3 + 8 = 11 \checkmark \]Trying values of x in 3x + 8 = 11
| x | 3x + 8 | Equals 11? |
|---|---|---|
| -1 | 5 | no |
| 0 | 8 | no |
| 1 | 11 | yes |
| 2 | 14 | no |
| 3 | 17 | no |
Questions
What is x in 3x + 8 = 11?
The solution of 3x + 8 = 11 is x = 1.
How do you solve 3x + 8 = 11?
Subtract 8 from both sides to get 3x = 3, then divide both sides by 3 to get x = 1.
How do I check the answer?
Replace x by 1: 3(1) + 8 = 11, which is 11.