How do you solve the system of equations #3x + 7y = 49# and #2x + 4y = 27#?

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Answer 1 · 2016-12-31T16:32:51

#y=27/2,x=-27/2#

#3x+7y=49#

#2x+4y=27#

#3x+7y=49----a#

#2x+4y=27----b#

#6x+14y=98----#a * 2#----c #

#6x+12y=71----b * 3----d#

#2y=27------c-d#

#y=27/2#

substitute # y=27/2 #in --------b

#2x+4(27/2)=27#

#2x+54=27#

#2x=27-54#

#2x=-27#

#x=-27/2#

substitute #y=27/2,x=-27/2# in --------b

#2(-27/2)+4(27/2)=27#

#-27+54=27#

#27=27#