Question

If x+y=10 and xy=21, find 2(x^2+y^2)​

Answer 1

Step-by-step explanation:

(x+y)^2= x^2+y^2 +2xy

10^2 = x^2+y^2 +2(21)

x^2+y^2 = 100 -42

x^2+y^2 = 58

THerefore

2(x^2+y^2)

2(58)

116 (Ans)

Answer 2

Answer:  x+y= 10   xy=21  so

Step-by-step explanation: (x^2+y^2)= (x+y)^2-2xy  = (10)^2-2(21)=  58

so 2(x^2+y^2)  = 2(58) = 116