Solve 7x − 7 = −42

The solution of 7x − 7 = −42 is x = -5.

7x - 7 = -42\ \Rightarrow\ x = -5

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

The lines y = 7x − 7 and y = -42 meet at x = -5. 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.
$7x - 7 = -42$
2
Add 7 to both sides:
$7x - 7 + 7 = -42 + 7 \ \Rightarrow\ 7x = -35$
3
Divide both sides by 7:
$\frac{7x}{7} = \frac{-35}{7} \ \Rightarrow\ x = -5$
4
Check: put x = -5 back into the equation.
$7\cdot(-5) - 7 = -35 - 7 = -42 \checkmark$

LaTeX source of the formulas on this page

\[ 7x - 7 = -42\ \Rightarrow\ x = -5 \]
\[ 7x - 7 = -42 \]
\[ 7x - 7 + 7 = -42 + 7 \ \Rightarrow\ 7x = -35 \]
\[ \frac{7x}{7} = \frac{-35}{7} \ \Rightarrow\ x = -5 \]
\[ 7\cdot(-5) - 7 = -35 - 7 = -42 \checkmark \]

Trying values of x in 7x − 7 = −42

x	7x − 7	Equals -42?
-7	-56	no
-6	-49	no
-5	-42	yes
-4	-35	no
-3	-28	no

Questions

What is x in 7x − 7 = −42?

The solution of 7x − 7 = −42 is x = -5.

How do you solve 7x − 7 = −42?

Add 7 to both sides to get 7x = -35, then divide both sides by 7 to get x = -5.

How do I check the answer?

Replace x by -5: 7(-5) − 7 = -42, which is -42.

Solve 7x − 7 = −42

How to work it out

Trying values of x in 7x − 7 = −42

Questions

Similar equations