Solve 3x + 10 = ā20
The solution of 3x + 10 = ā20 is x = -10.
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 10 from both sides:
- 3
Divide both sides by 3:
- 4
Check: put x = -10 back into the equation.
LaTeX source of the formulas on this page
\[ 3x + 10 = -20\ \Rightarrow\ x = -10 \]
\[ 3x + 10 = -20 \]
\[ 3x + 10 - 10 = -20 - 10 \ \Rightarrow\ 3x = -30 \]
\[ \frac{3x}{3} = \frac{-30}{3} \ \Rightarrow\ x = -10 \]
\[ 3\cdot(-10) + 10 = -30 + 10 = -20 \checkmark \]Trying values of x in 3x + 10 = ā20
| x | 3x + 10 | Equals -20? |
|---|---|---|
| -12 | -26 | no |
| -11 | -23 | no |
| -10 | -20 | yes |
| -9 | -17 | no |
| -8 | -14 | no |
Questions
What is x in 3x + 10 = ā20?
The solution of 3x + 10 = ā20 is x = -10.
How do you solve 3x + 10 = ā20?
Subtract 10 from both sides to get 3x = -30, then divide both sides by 3 to get x = -10.
How do I check the answer?
Replace x by -10: 3(-10) + 10 = -20, which is -20.