Solve 12x + 15 = 219
The solution of 12x + 15 = 219 is x = 17.
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 15 from both sides:
- 3
Divide both sides by 12:
- 4
Check: put x = 17 back into the equation.
LaTeX source of the formulas on this page
\[ 12x + 15 = 219\ \Rightarrow\ x = 17 \]
\[ 12x + 15 = 219 \]
\[ 12x + 15 - 15 = 219 - 15 \ \Rightarrow\ 12x = 204 \]
\[ \frac{12x}{12} = \frac{204}{12} \ \Rightarrow\ x = 17 \]
\[ 12\cdot17 + 15 = 204 + 15 = 219 \checkmark \]Trying values of x in 12x + 15 = 219
| x | 12x + 15 | Equals 219? |
|---|---|---|
| 15 | 195 | no |
| 16 | 207 | no |
| 17 | 219 | yes |
| 18 | 231 | no |
| 19 | 243 | no |
Questions
What is x in 12x + 15 = 219?
The solution of 12x + 15 = 219 is x = 17.
How do you solve 12x + 15 = 219?
Subtract 15 from both sides to get 12x = 204, then divide both sides by 12 to get x = 17.
How do I check the answer?
Replace x by 17: 12(17) + 15 = 219, which is 219.