Solve 9x − 11 = 169

The solution of 9x − 11 = 169 is x = 20.

9x - 11 = 169\ \Rightarrow\ x = 20

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

The lines y = 9x − 11 and y = 169 meet at x = 20. 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.
$9x - 11 = 169$
2
Add 11 to both sides:
$9x - 11 + 11 = 169 + 11 \ \Rightarrow\ 9x = 180$
3
Divide both sides by 9:
$\frac{9x}{9} = \frac{180}{9} \ \Rightarrow\ x = 20$
4
Check: put x = 20 back into the equation.
$9\cdot20 - 11 = 180 - 11 = 169 \checkmark$

LaTeX source of the formulas on this page

\[ 9x - 11 = 169\ \Rightarrow\ x = 20 \]
\[ 9x - 11 = 169 \]
\[ 9x - 11 + 11 = 169 + 11 \ \Rightarrow\ 9x = 180 \]
\[ \frac{9x}{9} = \frac{180}{9} \ \Rightarrow\ x = 20 \]
\[ 9\cdot20 - 11 = 180 - 11 = 169 \checkmark \]

Trying values of x in 9x − 11 = 169

x	9x − 11	Equals 169?
18	151	no
19	160	no
20	169	yes
21	178	no
22	187	no

Questions

What is x in 9x − 11 = 169?

The solution of 9x − 11 = 169 is x = 20.

How do you solve 9x − 11 = 169?

Add 11 to both sides to get 9x = 180, then divide both sides by 9 to get x = 20.

How do I check the answer?

Replace x by 20: 9(20) − 11 = 169, which is 169.

Solve 9x − 11 = 169

How to work it out

Trying values of x in 9x − 11 = 169

Questions

Similar equations