How do you solve #7x-2y=8# and #5x+2y=4# using substitution?

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Answer 1 · 2018-05-07T12:39:01

Find #2y# in the first and put the value in the second equation

#7x-8 = 2y# after arranging the first original equation. Put this into the second

#5x + 2y = 4#

#5x + 7x - 8 = 4#

#12x = 4+8#

#x = 12/12 = 1#

Now find y.

#2y=7x-8#

#2y = 7-8#

#2y = -1#

#y=-1/2#

Your answer is #x=1# and #y=-1/2#