Solve 5x − 9 = −39

The solution of 5x − 9 = −39 is x = -6.

5x - 9 = -39\ \Rightarrow\ x = -6

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

The lines y = 5x − 9 and y = -39 meet at x = -6. 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.
$5x - 9 = -39$
2
Add 9 to both sides:
$5x - 9 + 9 = -39 + 9 \ \Rightarrow\ 5x = -30$
3
Divide both sides by 5:
$\frac{5x}{5} = \frac{-30}{5} \ \Rightarrow\ x = -6$
4
Check: put x = -6 back into the equation.
$5\cdot(-6) - 9 = -30 - 9 = -39 \checkmark$

LaTeX source of the formulas on this page

\[ 5x - 9 = -39\ \Rightarrow\ x = -6 \]
\[ 5x - 9 = -39 \]
\[ 5x - 9 + 9 = -39 + 9 \ \Rightarrow\ 5x = -30 \]
\[ \frac{5x}{5} = \frac{-30}{5} \ \Rightarrow\ x = -6 \]
\[ 5\cdot(-6) - 9 = -30 - 9 = -39 \checkmark \]

Trying values of x in 5x − 9 = −39

x	5x − 9	Equals -39?
-8	-49	no
-7	-44	no
-6	-39	yes
-5	-34	no
-4	-29	no

Questions

What is x in 5x − 9 = −39?

The solution of 5x − 9 = −39 is x = -6.

How do you solve 5x − 9 = −39?

Add 9 to both sides to get 5x = -30, then divide both sides by 5 to get x = -6.

How do I check the answer?

Replace x by -6: 5(-6) − 9 = -39, which is -39.

Solve 5x − 9 = −39

How to work it out

Trying values of x in 5x − 9 = −39

Questions

Similar equations