How do you solve the system of equations #-5x + 3y = 51# and #y = 10x - 8#?

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Answer 1 · 2016-11-15T05:02:39

#x=3# and #y=22#

Replace #y# in the first equation with the value of #y# from the second equation which is #color(red)((10x-8))#.

#-5x+3color(red)((10x-8))=51#

Open the brackets and simplify. The product of a positive and a negative is a negative.

#-5x+30x-24=51#

#25x-24=51#

Add #24# to both sides.

#25x=75#

Divide both sides by #25#.

#x=75/25#

#x=3#

Now replace #x# in the second equation with #3#.

#color(red)(y=(10xx3)-8)#

Open the bracket and simplify.

#color(red)(y=30-8)#

#color(red)(y=22)#