Think of it as a old of scales or a balance beam.
The equals sign means each side is the same. Then whatever you do to one side do the same to the other, ie subtract or add 7, divide each side by 2 etc until you have whats you want on one side which will equal the remainder on the other side.
Ie y= 7-2x
Add 2x to each side
Gets you y+ 2x = 7
Take y from each side
Gets you 2x =7-y
Divide each side by 2
Gets you x= 7-y / 2
( that is 7-y all divided by 2 )
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Last edited by bingofuel; 21st April 2016 at 21:09.
Reason: To add the working