Question

How do you find the domain of `y =(8-x) /( x+4)`?

Answer 1

`x inRR,x!=-4`

Explanation:

The denominator of y cannot be zero as this would make y undefined. Equating the denominator to zero and solving gives the value that x cannot be.

`"solve "x+4=0rArrx=-4larrcolor(red)"excluded value"`

`"domain is "x inRR,x!=-4`

`x in(-oo,-4)uu(-4,oo)larrcolor(blue)"in interval notation"`
graph{(8-x)/(x+4) [-10, 10, -5, 5]}