You can put this solution on YOUR website! If the sum of 60% of a fractional number and the numbers's square root is 5 greater than one fifth of the number then the number is ?
:
Let n = the fractional number
.6n + = n + 5
We can write 1/5 as .2
.6n + =.2n + 5
subtract .6n from both sides = .2n - .6n + 5 = -.4n + 5
square both sides
n = (-.4n+5)^2
n = .16n^2 - 2n - 2n + 25
n = .16n^2 - 4n + 25
0 = .16n^2 - 4n - n + 25
A quadratic equation
.16n^2 - 5n + 25 = 0
using the quadratic formula; a=.16; b=-5; c=25
I got two solution, but only one was fractional
n = 6.25 or 6 is the number
:
:
you can confirm this for yourself, replace n with 6.25 in the original equation
.6(6.25) + = (6.25) + 5
