Question

For what value of x is the rational expression below undefined?

Answer 1

Answer: The expression is undefined for x=4 and x=5.

The expression is undefined for any x that makes the denominator 0. This leads to solving a quadratic equation:

$\frac{x+3}{x^2-9x+20}\\x^2-9x+20\neq 0\\x_{1,2}\neq\frac{9\pm\sqrt{9^2-80}}{2}=\frac{9\pm1}{2}\\x_1\neq4\\x_2\neq5$

Answer 2

Answer:

Step-by-step explanation:

Alright, lets get started.

The rational expression is gien as :

$\frac{x+3}{x^2-9x+20}$

For being the function undefined, the denominator must be equal to zero.

$x^2 -9x +20=0$

factoring

$(x-5)(x-4)=0$

This will give two values of x, which are

x = 5 and x = 4

So,the answer is 4 and 5.   :   Answer

Hope it will help :)