How do you simplify (x+5)/(3x^2+14x-5) and what are the excluded values of the variables?
1 Answer
Mar 18, 2018
Explanation:
"factorise the denominator using the a-c method"
"the factors of - 15 which sum to + 14 are + 15 and - 1"
3x^2+15x-x-5larrcolor(blue)"split the middle term"
=color(red)(3x)(x+5)color(red)(-1)(x+5)larrcolor(blue)"factor by grouping"
"take out "color(blue)"common factor "(x+5)
=(x+5)(color(red)(3x-1))
rArr(cancel((x+5)))/(cancel((x+5))(3x-1))
=1/(3x-1)
"the excluded values are any values of x which make "
"the denominator zero"
3x-1=0rArrx=1/3larrcolor(red)"excluded value"
