Question

Find the value of x-y when x+y=-9 and xy =20

Answer 1

Answer:

1or-1is the correct answer. i hope this will help you

Answer 2

Answer:

x=9-y

9y-y2=20

Therefore

y2-9y-20=0

y2-4y-5y-20=0

y[y-4]-5[y-4]=0

y=4

x=5

Therefore

x-y= 5-4= 1