How do you solve 9x - 3y = 3 and 3x + 8y = -17?

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Answer 1 · 2015-09-05T07:29:51

The solution is
#color(blue)(x=-1/3, y=-2#

#color(blue)(9x) - 3y = 3#..........equation #1#

#3x + 8y = -17#, multiplying the equation by #3#
#color(blue)(9x) + 24y = -51#......equation #2#

Solving by elimination .
Subtracting equation #2# from #1# results in elimination of #color(blue)(9x#

#cancelcolor(blue)(9x) - 3y = 3#

#-cancelcolor(blue)(9x) - 24y = +51#

#-27y =54#
#color(blue)(y=-2#

Finding #x# by substituting #y# in equation #1#
#9x - 3y = 3#

#x = (3+3y)/9#

#x = (3+3*(-2))/9#

#x = (3-6)/9#

#x = (-3)/9#

#color(blue)(x =-1/3#