Solve 5x − 5 = 70

The solution of 5x − 5 = 70 is x = 15.

5x - 5 = 70\ \Rightarrow\ x = 15

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

The lines y = 5x − 5 and y = 70 meet at x = 15. 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.
$5x - 5 = 70$
2
Add 5 to both sides:
$5x - 5 + 5 = 70 + 5 \ \Rightarrow\ 5x = 75$
3
Divide both sides by 5:
$\frac{5x}{5} = \frac{75}{5} \ \Rightarrow\ x = 15$
4
Check: put x = 15 back into the equation.
$5\cdot15 - 5 = 75 - 5 = 70 \checkmark$

LaTeX source of the formulas on this page

\[ 5x - 5 = 70\ \Rightarrow\ x = 15 \]
\[ 5x - 5 = 70 \]
\[ 5x - 5 + 5 = 70 + 5 \ \Rightarrow\ 5x = 75 \]
\[ \frac{5x}{5} = \frac{75}{5} \ \Rightarrow\ x = 15 \]
\[ 5\cdot15 - 5 = 75 - 5 = 70 \checkmark \]

Trying values of x in 5x − 5 = 70

x	5x − 5	Equals 70?
13	60	no
14	65	no
15	70	yes
16	75	no
17	80	no

Questions

What is x in 5x − 5 = 70?

The solution of 5x − 5 = 70 is x = 15.

How do you solve 5x − 5 = 70?

Add 5 to both sides to get 5x = 75, then divide both sides by 5 to get x = 15.

How do I check the answer?

Replace x by 15: 5(15) − 5 = 70, which is 70.

Solve 5x − 5 = 70

How to work it out

Trying values of x in 5x − 5 = 70

Questions

Similar equations