Solve 8x − 9 = 63

The solution of 8x − 9 = 63 is x = 9.

8x - 9 = 63\ \Rightarrow\ x = 9

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

The lines y = 8x − 9 and y = 63 meet at x = 9. 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.
$8x - 9 = 63$
2
Add 9 to both sides:
$8x - 9 + 9 = 63 + 9 \ \Rightarrow\ 8x = 72$
3
Divide both sides by 8:
$\frac{8x}{8} = \frac{72}{8} \ \Rightarrow\ x = 9$
4
Check: put x = 9 back into the equation.
$8\cdot9 - 9 = 72 - 9 = 63 \checkmark$

LaTeX source of the formulas on this page

\[ 8x - 9 = 63\ \Rightarrow\ x = 9 \]
\[ 8x - 9 = 63 \]
\[ 8x - 9 + 9 = 63 + 9 \ \Rightarrow\ 8x = 72 \]
\[ \frac{8x}{8} = \frac{72}{8} \ \Rightarrow\ x = 9 \]
\[ 8\cdot9 - 9 = 72 - 9 = 63 \checkmark \]

Trying values of x in 8x − 9 = 63

x	8x − 9	Equals 63?
7	47	no
8	55	no
9	63	yes
10	71	no
11	79	no

Questions

What is x in 8x − 9 = 63?

The solution of 8x − 9 = 63 is x = 9.

How do you solve 8x − 9 = 63?

Add 9 to both sides to get 8x = 72, then divide both sides by 8 to get x = 9.

How do I check the answer?

Replace x by 9: 8(9) − 9 = 63, which is 63.

Solve 8x − 9 = 63

How to work it out

Trying values of x in 8x − 9 = 63

Questions

Similar equations