Question

If x-y=5,xy=84,find x+y

Answer 1

Nadha1 Ambitious

x-y=5

xy=84

x=5+y

sub x value in xy=84

(5+y)y=84

y2+5y=84

y2+5y-84=0

y=-12 and 7

sub y=-12 in x-y=5

x+12=5

x=5-12=-7

sub y=7 in x-y=5

x-7=5

x=5+7=12

so,

x=-7,12

y=-12,7

Answer 2

Step-by-step explanation:

x - y = 5

here

12 - 7 =5

so

12×7=84

therefore

7+12=19