Rational Review

Which of the following tables represents a direct variation?

• X: 2, 4, 10, 12; Y: 4, 8, 20, 24

• X: 1, 2, 4, 8; Y: 8, 4, 2, 1

• X: 2, 3, 4, 5; Y: 30, 20, 15, 12

• X: 3, 6, 12, 15; Y: 1, 2, 4, 5

• y = 0

• y = 1

• y = -2

• y = 2

• y = 0

• y = 3

• y = 4

• y = -4

A rational equation that has been horizontally stretched by 4 and reflected over the x-axis can be written in the form g(x) = ± \frac{a}{b(x-h)} + k. What is the value of 'a'?

• A) 4

• B) -4

• C) 1

• D) -1

What is the horizontal asymptote (HA) of the function f(x) = \frac{2}{x+1} - 4?

• y = 0

• y = -4

• y = 2

• y = 1

Fill in the blank: A rational equation that has been horizontally compressed by a factor of 2, shifted down 2 and right 1 is written as g(x) = \frac{a}{b(x-h)} + k. What is the value of h?

• 0

• 1

• 2

• 3

The time (t) it takes you to get to campus varies inversely as your driving speed (s). Averaging 20 miles per hour in bad traffic, it takes you 1.5 hours to get to campus. How long would the trip take averaging 50 miles per hour?

• 0.6 hours

• 1 hour

• 1.5 hours

• 2 hours

A rational equation that has been vertically stretched by a factor of 2, with a horizontal asymptote of y = -1, and a vertical asymptote at x=4. Fill in the blank: The equation is g(x) = ± a/(b(x-h)) + k, where a = 2, h = 4, and k = ____.

• A) 0

• B) 1

• C) -1

• D) 2