# How do you solve -11.2+4(2.1+q)=-0.8?

Aug 5, 2016

$q = 0.5$

#### Explanation:

Given:$\text{ } - 11.2 + 4 \left(2.1 + q\right) = - 0.8$

Lets get rid of the decimals; multiply everything by $\textcolor{b l u e}{10}$

$\textcolor{b r o w n}{\textcolor{b l u e}{10} \left[- 11.2 + 4 \left(2.1 + q\right)\right] = \textcolor{b l u e}{10} \left(- 0.8\right)}$

$- 112 + 4 \left(21 + 10 q\right) = - 8$

Add $112$ to both sides

$4 \left(21 + 10 q\right) = 104$

Divide both sides by 4

$21 + 10 q = 26$

Subtract 21 from both sides

$10 q = 5$

Divide both sides by 10

$q = 0.5$
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check:
-11.2+4(2.1+0.5)=-0.8$\textcolor{red}{\leftarrow \text{ Solution confirmed}}$