x squared + y squared =20 xy=2 then x-y=??

Answer 1

(x-y)^2 = x^2 + y^2 - 2xy = 16
then x - y = ± 4

depending on which of the variables is greater.


d:

Answer 2

Hello,

Take xy =2 times -2 giving us -xy = -4 and add the two together giving us.

x^2 -2xy + y^2 = 16 now factor and we have (x-y)^2 = 16 take the square root of both sides giving us; x-y = +/- 4

Hope This Helps!

Answer 3

(x- y) ^ 2 = x^ 2 - 2xy + y^2 = 20 - 4 = 16
x - y = 4 or x - y = -4