Solve 12x − 3 = −39

The solution of 12x − 3 = −39 is x = -3.

12x - 3 = -39\ \Rightarrow\ x = -3

Explain it step by step in chat Make a short video of it

The lines y = 12x − 3 and y = -39 meet at x = -3. The solution of the equation is the x-coordinate of the point where the two sides are equal.

How to work it out

1
The goal is to get x alone. Undo the operations in the opposite order: first the subtraction, then the multiplication.
$12x - 3 = -39$
2
Add 3 to both sides:
$12x - 3 + 3 = -39 + 3 \ \Rightarrow\ 12x = -36$
3
Divide both sides by 12:
$\frac{12x}{12} = \frac{-36}{12} \ \Rightarrow\ x = -3$
4
Check: put x = -3 back into the equation.
$12\cdot(-3) - 3 = -36 - 3 = -39 \checkmark$

LaTeX source of the formulas on this page

\[ 12x - 3 = -39\ \Rightarrow\ x = -3 \]
\[ 12x - 3 = -39 \]
\[ 12x - 3 + 3 = -39 + 3 \ \Rightarrow\ 12x = -36 \]
\[ \frac{12x}{12} = \frac{-36}{12} \ \Rightarrow\ x = -3 \]
\[ 12\cdot(-3) - 3 = -36 - 3 = -39 \checkmark \]

Trying values of x in 12x − 3 = −39

x	12x − 3	Equals -39?
-5	-63	no
-4	-51	no
-3	-39	yes
-2	-27	no
-1	-15	no

Questions

What is x in 12x − 3 = −39?

The solution of 12x − 3 = −39 is x = -3.

How do you solve 12x − 3 = −39?

Add 3 to both sides to get 12x = -36, then divide both sides by 12 to get x = -3.

How do I check the answer?

Replace x by -3: 12(-3) − 3 = -39, which is -39.

Solve 12x − 3 = −39

How to work it out

Trying values of x in 12x − 3 = −39

Questions

Similar equations