How do you simplify #f( x ) = \frac { x + 9} { x ^ { 2} + 9x }#?

2 Answers
Dec 7, 2017

#f(x)=1/x=x^(-1)#

Explanation:

The denominator can be factorised into #x(x+9)#

Now, #f(x)=(x+9)/(x(x+9))#

#f(x)=cancel((x+9))/(x(cancel(x+9)))=1/x=x^(-1)#

Dec 7, 2017

#f(x)=1/x#

Explanation:

#"factorise the denominator and cancel common factor"#

#f(x)=cancel((x+9))/(xcancel((x+9))#

#color(white)(f(x))=1/xto(x!=0)#