Solve 3x + 8 = 56

The solution of 3x + 8 = 56 is x = 16.

3x + 8 = 56\ \Rightarrow\ x = 16

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

The lines y = 3x + 8 and y = 56 meet at x = 16. 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.
$3x + 8 = 56$
2
Subtract 8 from both sides:
$3x + 8 - 8 = 56 - 8 \ \Rightarrow\ 3x = 48$
3
Divide both sides by 3:
$\frac{3x}{3} = \frac{48}{3} \ \Rightarrow\ x = 16$
4
Check: put x = 16 back into the equation.
$3\cdot16 + 8 = 48 + 8 = 56 \checkmark$

LaTeX source of the formulas on this page

\[ 3x + 8 = 56\ \Rightarrow\ x = 16 \]
\[ 3x + 8 = 56 \]
\[ 3x + 8 - 8 = 56 - 8 \ \Rightarrow\ 3x = 48 \]
\[ \frac{3x}{3} = \frac{48}{3} \ \Rightarrow\ x = 16 \]
\[ 3\cdot16 + 8 = 48 + 8 = 56 \checkmark \]

Trying values of x in 3x + 8 = 56

x	3x + 8	Equals 56?
14	50	no
15	53	no
16	56	yes
17	59	no
18	62	no

Questions

What is x in 3x + 8 = 56?

The solution of 3x + 8 = 56 is x = 16.

How do you solve 3x + 8 = 56?

Subtract 8 from both sides to get 3x = 48, then divide both sides by 3 to get x = 16.

How do I check the answer?

Replace x by 16: 3(16) + 8 = 56, which is 56.

Solve 3x + 8 = 56

How to work it out

Trying values of x in 3x + 8 = 56

Questions

Similar equations