Solve 8x − 4 = 116

The solution of 8x − 4 = 116 is x = 15.

8x - 4 = 116\ \Rightarrow\ x = 15

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

The lines y = 8x − 4 and y = 116 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.
$8x - 4 = 116$
2
Add 4 to both sides:
$8x - 4 + 4 = 116 + 4 \ \Rightarrow\ 8x = 120$
3
Divide both sides by 8:
$\frac{8x}{8} = \frac{120}{8} \ \Rightarrow\ x = 15$
4
Check: put x = 15 back into the equation.
$8\cdot15 - 4 = 120 - 4 = 116 \checkmark$

LaTeX source of the formulas on this page

\[ 8x - 4 = 116\ \Rightarrow\ x = 15 \]
\[ 8x - 4 = 116 \]
\[ 8x - 4 + 4 = 116 + 4 \ \Rightarrow\ 8x = 120 \]
\[ \frac{8x}{8} = \frac{120}{8} \ \Rightarrow\ x = 15 \]
\[ 8\cdot15 - 4 = 120 - 4 = 116 \checkmark \]

Trying values of x in 8x − 4 = 116

x	8x − 4	Equals 116?
13	100	no
14	108	no
15	116	yes
16	124	no
17	132	no

Questions

What is x in 8x − 4 = 116?

The solution of 8x − 4 = 116 is x = 15.

How do you solve 8x − 4 = 116?

Add 4 to both sides to get 8x = 120, then divide both sides by 8 to get x = 15.

How do I check the answer?

Replace x by 15: 8(15) − 4 = 116, which is 116.

Solve 8x − 4 = 116

How to work it out

Trying values of x in 8x − 4 = 116

Questions

Similar equations