Answer:
The number of ducks are 9.
Step-by-step explanation:
There are x ducks in a pond.
The number of swans in the pond is equal to the square root of the number of ducks.
Means swans = [tex]\sqrt{x}[/tex]
If the total number of swans and ducks in the pond is 12.
[tex]x+ \sqrt{x} =12[/tex]
=> [tex]\sqrt{x} =12-x[/tex]
Squaring both sides, we get
[tex]x=x^{2} +144-24x[/tex]
=> Taking everything on one side and equating to 0
[tex]x^{2} -x-24x+144=0[/tex]
=> [tex]x^{2}-25x+144=0[/tex]
=> Solving this we get, x = 9 and x = -16
So, we have number of ducks as 9.
And number of swans = [tex]\sqrt{9} =3[/tex]