Solve? #2x-10y=-20 and -x+4y=28#

2 Answers

#10y=2x+20# and #4y=x+28#.

Yielding, #x=-100# and #y=-18#

Explanation:

Now multiply the second equation (by #-2#) and add equations:

#" "10y=+2x+20#
#" "ul(-8y=-2x-56#
#" "2y=" "-36" "# there is only #y#

Therefore #y=-18#

Now you can calculate# x# by using either (original) equation
I have chosen the 2nd original equation.

#-x-72=28#

#-x=100#. In other words,

#x=-100#

Your answer: #x=-100# and #y=-18#

Apr 25, 2017

I got:
#x=-100#
#y=-18#

Explanation:

I tryed multiplying the second equation by #2# and adding to the first:
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