# Question #0ac33

Feb 23, 2017

$\textcolor{b l u e}{\text{Making "y" the dependant variable}}$

Divide both sides by 4

$\frac{4}{4} y = \frac{1.4}{4} x - \frac{1}{4}$

But $\frac{4}{4} = 1$

$y = \frac{1.4}{4} x - \frac{1}{4}$

But $\frac{1.4}{4}$ is the same as $\frac{1.4 \times 10}{4 \times 10} = \frac{14}{40} = \frac{14 \div 2}{40 \div 2} = \frac{7}{20}$

$\textcolor{g r e e n}{y = \frac{7}{20} x = \frac{1}{4}}$
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$\textcolor{b l u e}{\text{Making "x" the dependant variable}}$

I am a bit fed up with the decimal so lets get rid of it.
Multiply everything by 10

$40 y = 14 x - 10$

$40 y + 10 = 14 x - 10 + 10$

But -10+10=0

$40 y + 10 = 14 x$

Divide both sides (everything) by 14

$\frac{40}{14} y + \frac{10}{14} = \frac{14}{14} \times x$

$\frac{20}{7} y + \frac{5}{7} = x$

Write as:

$\textcolor{g r e e n}{x = \frac{20}{7} y + \frac{5}{7}}$
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Substitute any known value into these and you have you answer, However, no known values provided in the question.