Solve 8x + 13 = −43

The solution of 8x + 13 = −43 is x = -7.

8x + 13 = -43\ \Rightarrow\ x = -7

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

The lines y = 8x + 13 and y = -43 meet at x = -7. 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 addition, then the multiplication.
$8x + 13 = -43$
2
Subtract 13 from both sides:
$8x + 13 - 13 = -43 - 13 \ \Rightarrow\ 8x = -56$
3
Divide both sides by 8:
$\frac{8x}{8} = \frac{-56}{8} \ \Rightarrow\ x = -7$
4
Check: put x = -7 back into the equation.
$8\cdot(-7) + 13 = -56 + 13 = -43 \checkmark$

LaTeX source of the formulas on this page

\[ 8x + 13 = -43\ \Rightarrow\ x = -7 \]
\[ 8x + 13 = -43 \]
\[ 8x + 13 - 13 = -43 - 13 \ \Rightarrow\ 8x = -56 \]
\[ \frac{8x}{8} = \frac{-56}{8} \ \Rightarrow\ x = -7 \]
\[ 8\cdot(-7) + 13 = -56 + 13 = -43 \checkmark \]

Trying values of x in 8x + 13 = −43

x	8x + 13	Equals -43?
-9	-59	no
-8	-51	no
-7	-43	yes
-6	-35	no
-5	-27	no

Questions

What is x in 8x + 13 = −43?

The solution of 8x + 13 = −43 is x = -7.

How do you solve 8x + 13 = −43?

Subtract 13 from both sides to get 8x = -56, then divide both sides by 8 to get x = -7.

How do I check the answer?

Replace x by -7: 8(-7) + 13 = -43, which is -43.

Solve 8x + 13 = −43

How to work it out

Trying values of x in 8x + 13 = −43

Questions

Similar equations