How do you solve -x+5y=8 and 3x+ 7y=2 with elimination?

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Answer 1 · 2018-07-03T16:08:05

The solutions are #x=-23/11# and #y=13/11#

There are #2# equations.

#-x+5y=8#.....................#(1)#

#3x+7y=2#.......................... #(2)#

From equation #(1)#, calculate #x#

#x=5y-8#

Substitute this value of #x# in equation #(2)# and solve for #y#

#3(5y-8)+7y=2#

#=>#, #15y-24+7y=2#

#=>#, #22y=2+24#

#=>#, #22y=26#

#=>#, #y=26/22=13/11#

Therefore,

#x=5y-8=5*13/11-8#

#=65/11-8#

#=(65-88)/11#

#=-23/11#

Therefore,

Verification, in equation #(2)#

#3*-23/11+7*13/11=-69/11+91/11=22/11=2#

#ok#

Verification, in equation #(1)#

#5*13/11-8=65/11-88/11=-23/11=x#

#ok#