Solve 3x − 13 = −43

The solution of 3x − 13 = −43 is x = -10.

3x - 13 = -43\ \Rightarrow\ x = -10

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

The lines y = 3x − 13 and y = -43 meet at x = -10. 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.
$3x - 13 = -43$
2
Add 13 to both sides:
$3x - 13 + 13 = -43 + 13 \ \Rightarrow\ 3x = -30$
3
Divide both sides by 3:
$\frac{3x}{3} = \frac{-30}{3} \ \Rightarrow\ x = -10$
4
Check: put x = -10 back into the equation.
$3\cdot(-10) - 13 = -30 - 13 = -43 \checkmark$

LaTeX source of the formulas on this page

\[ 3x - 13 = -43\ \Rightarrow\ x = -10 \]
\[ 3x - 13 = -43 \]
\[ 3x - 13 + 13 = -43 + 13 \ \Rightarrow\ 3x = -30 \]
\[ \frac{3x}{3} = \frac{-30}{3} \ \Rightarrow\ x = -10 \]
\[ 3\cdot(-10) - 13 = -30 - 13 = -43 \checkmark \]

Trying values of x in 3x − 13 = −43

x	3x − 13	Equals -43?
-12	-49	no
-11	-46	no
-10	-43	yes
-9	-40	no
-8	-37	no

Questions

What is x in 3x − 13 = −43?

The solution of 3x − 13 = −43 is x = -10.

How do you solve 3x − 13 = −43?

Add 13 to 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) − 13 = -43, which is -43.

Solve 3x − 13 = −43

How to work it out

Trying values of x in 3x − 13 = −43

Questions

Similar equations