How do you solve #2x - y = 4# and #4x = 2y + 8#?

1 Answer
Don't Memorise
Apr 7, 2015

Dividing both sides of the second equation by 2, we get

#(4x)/2 = (2y)/2+8/2#

#2x = y + 4#

#2x-y = 4#

This is the same equation as the first one. It means that there are INFINITE solutions for #x# and #y#.
Any values of x and y that satisfy the first equation will also satisfy the second one.

For eg. if we choose x = 2, y = 0:

First equation :
#2x-y = 4#
#(2*2) - 0 = 4# (which is equal to the Right Hand Side)

Second equation :
#4x = 2y + 8#
Left Hand Side is #4x = 4*2 = 8#
And the Right Hand Side is #2y + 8 = (2*0) + 8 = 8#

Both the equations will be satisfied for various such values of #x and y# like #(3,2); (4,6)# and so on..

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