Solve 4x + 8 = 36

The solution of 4x + 8 = 36 is x = 7.

4x + 8 = 36\ \Rightarrow\ x = 7

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

The lines y = 4x + 8 and y = 36 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.
$4x + 8 = 36$
2
Subtract 8 from both sides:
$4x + 8 - 8 = 36 - 8 \ \Rightarrow\ 4x = 28$
3
Divide both sides by 4:
$\frac{4x}{4} = \frac{28}{4} \ \Rightarrow\ x = 7$
4
Check: put x = 7 back into the equation.
$4\cdot7 + 8 = 28 + 8 = 36 \checkmark$

LaTeX source of the formulas on this page

\[ 4x + 8 = 36\ \Rightarrow\ x = 7 \]
\[ 4x + 8 = 36 \]
\[ 4x + 8 - 8 = 36 - 8 \ \Rightarrow\ 4x = 28 \]
\[ \frac{4x}{4} = \frac{28}{4} \ \Rightarrow\ x = 7 \]
\[ 4\cdot7 + 8 = 28 + 8 = 36 \checkmark \]

Trying values of x in 4x + 8 = 36

x	4x + 8	Equals 36?
5	28	no
6	32	no
7	36	yes
8	40	no
9	44	no

Questions

What is x in 4x + 8 = 36?

The solution of 4x + 8 = 36 is x = 7.

How do you solve 4x + 8 = 36?

Subtract 8 from both sides to get 4x = 28, then divide both sides by 4 to get x = 7.

How do I check the answer?

Replace x by 7: 4(7) + 8 = 36, which is 36.

Solve 4x + 8 = 36

How to work it out

Trying values of x in 4x + 8 = 36

Questions

Similar equations