The required simplication of rational expression is -(4 + x) / (x - 5).
What is a rational number?
Any real number that can be represented in the form of p/q, where q is not equal to 0 is called a rational number. The decimal expansion of rational numbers is terminating and repeating.
Simplifying the rational expression, 12 - x - x² / x² - 8x + 15
Given a rational expression,
12 - x - x² / x² - 8x + 15
On simplifying, we get,
For numerator, 12 - x - x²: (3 - x)(4 + x)
For denominator, x² - 8x + 15: (x - 5)(x - 3)
Now, 12 - x - x² / x² - 8x + 15 = (3 - x)(4 + x) / (x - 5)(x - 3)
= -(4 + x) / (x - 5)
Restriction is that the denominator, x - 5 should not be 0.
Hence, the required simplication of rational expression is -(4 + x) / (x - 5)
To learn more about rational numbers, visit here:
https://brainly.com/question/12088221
#SPJ4