Solve 4x − 11 = 9

The solution of 4x − 11 = 9 is x = 5.

4x - 11 = 9\ \Rightarrow\ x = 5

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

The lines y = 4x − 11 and y = 9 meet at x = 5. 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.
$4x - 11 = 9$
2
Add 11 to both sides:
$4x - 11 + 11 = 9 + 11 \ \Rightarrow\ 4x = 20$
3
Divide both sides by 4:
$\frac{4x}{4} = \frac{20}{4} \ \Rightarrow\ x = 5$
4
Check: put x = 5 back into the equation.
$4\cdot5 - 11 = 20 - 11 = 9 \checkmark$

LaTeX source of the formulas on this page

\[ 4x - 11 = 9\ \Rightarrow\ x = 5 \]
\[ 4x - 11 = 9 \]
\[ 4x - 11 + 11 = 9 + 11 \ \Rightarrow\ 4x = 20 \]
\[ \frac{4x}{4} = \frac{20}{4} \ \Rightarrow\ x = 5 \]
\[ 4\cdot5 - 11 = 20 - 11 = 9 \checkmark \]

Trying values of x in 4x − 11 = 9

x	4x − 11	Equals 9?
3	1	no
4	5	no
5	9	yes
6	13	no
7	17	no

Questions

What is x in 4x − 11 = 9?

The solution of 4x − 11 = 9 is x = 5.

How do you solve 4x − 11 = 9?

Add 11 to both sides to get 4x = 20, then divide both sides by 4 to get x = 5.

How do I check the answer?

Replace x by 5: 4(5) − 11 = 9, which is 9.

Solve 4x − 11 = 9

How to work it out

Trying values of x in 4x − 11 = 9

Questions

Similar equations