Question

3(-4n - 9) = 21 plc solve ​

Answer 1

Answer:

$\huge{\boxed{n=-4}}$

Explanation:

$\begin{array}{cc}\begin{flushright}\text{Divide both sides of the equation by 3.}\end{flushright}&\begin{flushleft}-4n-9=7\end{flushleft}\\\begin{flushright}\text{Add 9 on both sides.}\end{flushright}&\begin{flushleft}-4n=16\end{flushleft}\\\begin{flushright}\text{Divide both sides by -4.}\end{flushrigh}&n=-4\end{array}$

Answer 2

Answer:

$\Huge \boxed{n=-4}$

Step-by-step explanation:

First thing you do is divide by 3 from both sides of equation.

$\displaystyle \frac{3(-4n-9)}{3}=\frac{21}{3}$

Simplify.

$\displaystyle -4n-9=7$

Then add by 9 from both sides of equation.

$\displaystyle -4n-9+9=7+9$

Simplify.

$\displaystyle 7+9=16$

$\displaystyle -4n=16$

Divide by -4 from both sides of equation.

$\displaystyle \frac{-4n}{-4}=\frac{16}{-4}$

Simplify, to find the answer.

$\displaystyle 16\div-4=-4$

$\huge\boxed{\textnormal{N=-4}}$, which is our answer.