How do you solve the following linear system: # 2x-5y=-4, -3x-8y=-1, #?

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Answer 1 · 2016-07-15T14:48:48

#x=-37#
#y=-14#

#2x-5y=-4" "(1)#
#color (red) (3) * (2x-5y)= color(red)(3) * (-4)#
#6x-15y=-12#

#color(green)(6x)=15y-12" "(3)#

#-3x-8y=-1" "(2)#
#color(red)(2) (-3x-8y)=color (red) (2) (-1)#
#-6x=-16y-2#

#color(green)(6x)=16y+2" "(4)#

#"we can write the equations (3) and (4) as equal"#

#15y-12=16y+2#
#-12-2=16y-15y#
#y=-14#

#"now let us use (1) or (2)"#
#2x-5(-14)=-4#
#2x+70=-4#
#2x=-70-4#
#2x=-74#
#x=-37#