Q14 - Geometry

Question

Find the value of the variable.

$-3b=-9$

Step-by-Step Solution

Answer

The value of the variable is $\mathit{b}\mathbf{=}\mathbf{3}$.

Step 1. Divide by 3.

To find the value of the variable b in the equation $-3b=-9$, divide both sides of the equation by 3.

$-\frac{3b}{3}=-\frac{9}{3}$

Step 2. Simplify the equation.

To further simplify, cancel the common factors of 3 on both sides.

$\begin{array}{l}-\frac{3b}{3}=-\frac{3\times 3}{3}\\ -b=-3\end{array}$

Step 3. Multiply by -1.

In order to obtain b, multiply the equation $-b=-3$ from both sides $-1$.

$\begin{array}{l}-b\times \left(-1\right)=-3\times \left(-1\right)\\ b=3\end{array}$ 

Step 4. Verify the value.

In order to verify the value of b, substitute 3 for b into the equation $-3b=-9$.

$\begin{array}{l}-3\times 3=-9\\ -9=-9\text{ True}\end{array}$

Hence, the value of the variable is $b=3$.