Write and solve an equation of ratios:
5 65
--- = ------
4 x
Then 5x = 260, or x = 52. There are 52 girls on the team. Note, as a check, that 65/52 reduces to 5/4, as it must.
A) 22.5 cm, 30 cm, and 37.5 cm
Divide 90 by 12 and multiply by three to check if any triplet has the answer in it. In this case only A
From the equation, we have

To find the vertex and focus, we have to use the following formula

And

So, we have


18n^6-20n^4+10n^3=
2n^3 (9n^3-10n+5)
Hope this helps :)