How do you evaluate #\frac { x ^ { 2} - 9} { x + 7} \div \frac { ( x + 3) } { 1}#?

1 Answer
Sep 13, 2017

#=1-10/(x+7)#

Explanation:

firstly, change using the rules of fractions change to a multiplication problem

#(x^2-9)/(x+7)-:(x+3)/1#

#=>(x^2-9)/(x+7)xx1/(x+3)#

secondly, factorise and cancel where possible

#(cancel((x+3))(x-3))/(x+7)xx1/cancel((x+3))#

#=(x-3)/(x+7)#

lastly change from an improper fraction

#=((x+7)-10)/(x+7)#

#=(x+7)/(x+7)-10/(x+7)#

#=1-10/(x+7)#