# 53 + 4 xx c = 21. What is c?

Mar 24, 2018

$c = - 8$

#### Explanation:

$53 + 4 \times c = 21$ is the same as $53 + 4 c = 21.$

(You cannot add 53 and 4 because of the order of operations)

Subtract $53$ from each side:

$\cancel{53} + 4 c - \cancel{53} = 21 - 53$

$4 c = - 32$

Divide each side by $4$ to get

$\frac{4 c}{4} = - \frac{32}{4}$

$c = - 8$

Mar 24, 2018

$c = - 8$

#### Explanation:

$53 + 4 \cdot c = 21$

$4 c = 21 - 53$

$4 c = - 32$

$c = - \frac{32}{4}$

$c = - 8$

$c = - 8$

:)

Mar 24, 2018

$c = - 8$

#### Explanation:

Notice that there are two terms on the left side.

$\textcolor{b l u e}{53} + \textcolor{red}{4 \times c} = 21$

Simplifying gives:$\text{ } \textcolor{b l u e}{53} + \textcolor{red}{4 c} = 21$
(Remember to multiply first)

$\textcolor{b l u e}{53} \mathmr{and} \textcolor{red}{4 c}$ are unlike terms and cannot be added.

To solve the equation:
isolate $\textcolor{red}{4 c}$ by subtracting $53$ on both sides.

$53 + 4 c - 53 = 21 - 53$

$4 c = - 32$

$c = - 8$