Xy-x^2= -20 x-2y=3 What is x and y?

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Answer 1 · 2018-05-14T12:34:27

Assuming you meant
#xy-x^2= -20#
#x-2y=3#
solutions are:
#(5,1)(-4,-7/2)#

equation 1
#xy-x^2= -20#

rearrange
#0=x^2-xy-20#

use cross method
#0=(x-5)(x+4)#
#:.x=5,x=-4#

substitute into equation 2
#x-2y=3#

if #x = 5#:
#5-2y=3#
#5-3=2y#
#2=2y#
#y=1#

if #x = -4#:
#-4-2y=3#
#-4-3=2y#
#-7=2y#
#y=-7/2#

solutions:
#(5,1)(-4,-7/2)#