Question

11. If x + y = 13 and xy = 6-, find —- )​

Answer 1

Answer:

x=13-y

xy=-6

13-y(y)=-6

13y-y2=-6

-y2+13y+6= 0

quadratic eqation

Answer 2

Answer:

x+y=6

squaring on both sides

(x+y)^2=6^2

x^2+y^2+2xy=36

x^2+y^2+2(-6)=36

x^2+y^2-12=36

x^2+y^2=24