Question #0ac33

1 Answer
Feb 23, 2017

color(blue)("Making "y" the dependant variable")

Divide both sides by 4

4/4y=1.4/4x-1/4

But 4/4=1

y=1.4/4x-1/4

But 1.4/4 is the same as (1.4xx10)/(4xx10) = 14/40 =(14-:2)/(40-:2)=7/20

color(green)(y=7/20x=1/4)
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color(blue)("Making "x" the dependant variable")

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

40y=14x-10

Add 10 to both sides

40y+10=14x-10+10

But -10+10=0

40y+10=14x

Divide both sides (everything) by 14

40/14y+10/14=14/14xx x

20/7y+5/7=x

Write as:

color(green)(x=20/7y+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.