Question 950020
If the sum of 60% of a fractional number and the number's square root is 5 greater than one fifth of the number, then the number is?
:
Write an equation for what it says (1/5 = .2)
{{{.6n + sqrt(n) = 5 + .2n}}}
: 
{{{sqrt(n) = 5 + .2n - .6n}}}
:
{{{sqrt(n) = 5 - .4n}}}
square both sides
n = (-.4n+5)^2
n = .16n^2 - 2n - 2n + 25
0  = .16n^2 - 4n - n + 25
A quadratic equation
 .16n - 5n + 25 = 0
using the quadratic formula; a=.16; b =-5; c=25
The fractional solution:
x = 6.25
:
:\
See if this check's out
{{{.6(6.25) + sqrt(6.25) = 5 + .2(6.25)}}}
3.75 + 2.5 = 5 + 1.25
6.25 = 6.25 confirms and also is our solution!