Question

if X + Y equal 4 and xy equal 2 find X square + Y square

Answer 1

given
x+y=4
xy=2
x^2+y^2=?
(x+y)^2=x^2+y^2+2xy
(4)^2=x2+y2+2×2
16=x2+y2+4
16-4=x2+y2
12=x2+y2

Answer 2

Here given (x+y) =4 & xy= 2

Here we will find (x²+y²) =????????

(x+y)²= x²+2xy+y²....... Equation (1)

But here given that x+y=4 & xy= 2, then

4²=x²+2(2)+y²

x²+y²= 16-4

Ur answer x²+y²=12