Question

If (x + y) = 9 and xy = 20, then find the value of x2 + y2​

Answer 1

Answer:

x^2+y^2=41

Step-by-step explanation:

x+y=9; xy=20

=> x+y=9 (squaring both sides)

=> (x+y)^2=(9)^2

=> x^2+y^2+2xy=81

=> x^2+y^2+2(20)=81
=> x^2+y^2=81-40

=> x^2+y^2=41