# How do you solve 5(1+4m)=2(3+10m)?

Feb 15, 2017

#### Explanation:

Multiply the content of each bracket by the number that is outside.

$\left(5 \times 1\right) + \left(5 \times 4 m\right) = \left(2 \times 3\right) + \left(2 \times 10 m\right)$

$5 + 20 m = 6 + 20 m$

Subtract $20 m$ from both sides giving

$5 = 6 \textcolor{red}{\leftarrow \text{ THIS IS VERY WRONG}}$
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$\textcolor{red}{\text{Suppose instead that you question was meant to be:}}$

$5 \left(1 - 4 m\right) = 2 \left(3 + 10 m\right)$

$5 - 20 m = 6 + 20 m$

Add $20 m$ to both sides

$5 - 20 m + 20 m = 6 + 20 m + 20 m$

$5 + 0 = 6 + 40 m$

Subtract 6 from both sides

$- 1 = 40 m$

Divide both sides by 40

$m = - \frac{1}{40}$