We have to identify the rational function among the given functions.
Rational function is a function that is the ratio of two polynomials. It is rational because one polynomial is divided by the other polynomial, like a ratio.
1. Consider the first function 
, since it is not a function that is the ratio of two polynomials. So, it is not a rational function.
2. Consider the second function 
, since it is not a function that is the ratio of two polynomials. So, it is not a rational function.
3. Consider the third function 
, since it is not a function that is the ratio of two polynomials. So, it is not a rational function.
4. Consider the fourth function 
, since it is a function that is the ratio of two polynomials (x+2) and (5x). So, it is a rational function.
So, Option D is the correct answer.
The slope of line D is also -4 because the lines are perpendicular.
Surface area of a square pyramid is the area of the base + 4 times the area of one of the slanted sides.
Area of base = side length * side length
Area of side = (1/2) * side length * slant height
Don't forget that you have to multiply the area of the side by 4!
Step 1: 12 x 12 = 144
Step 2: 12 x 20 = 240 divided by 2 = 120
Step 3: 144 + 120 x 4
The answer to 89+27+11 is 127
