Q21 of 50 Page 9

If x+y = 4 and xy=2, find the value of x2+y2

Given that,


x + y = 4


Squaring both sides, we get


(x + y)2 = 42


x2 + y2 + 2xy = 16


x2 + y2 + 2 (2) = 16


x2 + y2 = 16 – 4


x2 + y2 =12


More from this chapter

All 50 →
19

If =20, find the value of .

 20

If , find the values of and.

 22

If 3x+5y = 11 and xy = 2, find the value of 9x2+25y2

 23

If find the value of .