Solve 7x + 13 = −43

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

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

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

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

LaTeX source of the formulas on this page

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

Trying values of x in 7x + 13 = −43

x	7x + 13	Equals -43?
-10	-57	no
-9	-50	no
-8	-43	yes
-7	-36	no
-6	-29	no

Questions

What is x in 7x + 13 = −43?

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

How do you solve 7x + 13 = −43?

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

How do I check the answer?

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

Solve 7x + 13 = −43

How to work it out

Trying values of x in 7x + 13 = −43

Questions

Similar equations