When f(x)=25-x^2 and g(x)= x+5, (f/g)(x)=___?

If f(x)=25-x^2 and g(x)=x+5, what is (f/g)(x)? Write your answer in simplest form.
When f(x)=25-x^2 and g(x)= x+5, (f/g)(x)=

1 Answer
Jun 28, 2018

#5-x#

Explanation:

#(f/g) x = f(x)/g(x)#

#f(x) = 25 - x^2#

difference of two squares identity: #a^2 - b^2 = (a+b)(a-b)#

#25 - x^2 = 5^2 - x^2#
# = (5+x)(5-x)#

#g(x) = x+5 or 5+x#

#f(x)/g(x) = ((5+x)(5-x))/(x+5)#

#= (5-x)/1 = 5-x#