Solve 4x + 9 = −27

The solution of 4x + 9 = −27 is x = -9.

4x + 9 = -27\ \Rightarrow\ x = -9

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

The lines y = 4x + 9 and y = -27 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 addition, then the multiplication.
$4x + 9 = -27$
2
Subtract 9 from both sides:
$4x + 9 - 9 = -27 - 9 \ \Rightarrow\ 4x = -36$
3
Divide both sides by 4:
$\frac{4x}{4} = \frac{-36}{4} \ \Rightarrow\ x = -9$
4
Check: put x = -9 back into the equation.
$4\cdot(-9) + 9 = -36 + 9 = -27 \checkmark$

LaTeX source of the formulas on this page

\[ 4x + 9 = -27\ \Rightarrow\ x = -9 \]
\[ 4x + 9 = -27 \]
\[ 4x + 9 - 9 = -27 - 9 \ \Rightarrow\ 4x = -36 \]
\[ \frac{4x}{4} = \frac{-36}{4} \ \Rightarrow\ x = -9 \]
\[ 4\cdot(-9) + 9 = -36 + 9 = -27 \checkmark \]

Trying values of x in 4x + 9 = −27

x	4x + 9	Equals -27?
-11	-35	no
-10	-31	no
-9	-27	yes
-8	-23	no
-7	-19	no

Questions

What is x in 4x + 9 = −27?

The solution of 4x + 9 = −27 is x = -9.

How do you solve 4x + 9 = −27?

Subtract 9 from both sides to get 4x = -36, then divide both sides by 4 to get x = -9.

How do I check the answer?

Replace x by -9: 4(-9) + 9 = -27, which is -27.

Solve 4x + 9 = −27

How to work it out

Trying values of x in 4x + 9 = −27

Questions

Similar equations