What are the excluded values for #y=(2x+5)/(x+5)#?

1 Answer
Mar 31, 2018

Answer:

The only excluded value is #x=-5#.

Explanation:

Excluded values occur when the denominator of a fraction equals zero.

In simpler terms, excluded fractions are when #x# makes it so that the bottom of the fraction is #0#.

This is because division by zero is not possible, so the value of #x# is excluded.

To solve for the excluded variable, simply take the denominator, set it equal to #0#, then solve for #x#. That will tell you what value of #x# will make the denominator #0#.

Here's what that looks like:

#x+5=0#

#x+5color(blue)-color(blue)5=0color(blue)-color(blue)5#

#xcolor(red)cancelcolor(black)(color(black)+5color(blue)-color(blue)5)=0color(blue)-color(blue)5#

#x=0color(blue)-color(blue)5#

#x=-5#

This is the excluded value for #x#. Hope this helped!