What are the excluded values for y=7/(5x-10)?

1 Answer
Mar 28, 2017

x=2

Explanation:

The only excluded values in this problem would be asymptotes, which are values of x that make the denominator equal to 0. Since we cannot divide by 0, this creates a point that is "undefined" or excluded.

In the case of this problem, we are looking for a value of x that makes 5*x-10 equal to zero. So let's set that up:
5x-10=0
color(white)(5x)+10color(white)(0)+10
5x=10
/5color(white)(x)/5
x=10/5 or 2

So, when x=2, the the denominator becomes equal to zero. So that's the value we must exclude to avoid an asymptote. We can confirm this using a graph
graph{y=7/(5x-10)}

See, the graph is getting closer and closer to x=2, but it can never reach that point.