Question

If x+y =12 and xy =27 then find tge value of x^3+y^3

Answer 1

Answer:

Step-by-step explanation:

Answer 2

xy=27

x=27/y

now substituting the value of x to the above equation

ie. x+y=12

    27/y+y=12

   27+y²/y=12

27+y²=12y

y²-12y+27=0

sum= -12

product=27

y²-3y-9y+27=0

y(y-3)-9(y-3)=0

(y-9)(y-3)=0

y=9

y=3

substituting the value o y in the first equation

x=27/3                  or           x=27/9

x=9                        or          x=3

x³+y³

when x=3 and y=9

3³+9³=27+729

=756

when x=9 and y= 3

9³+3³=729+27

=756

∴x³+y³=756

hope it helps