Question

What is the function for a table with a domain of 5, 10, 15, 20 and a range of 40, 80, 120, and 160

Answer 1

To find the range we need to find the vertex of the parabola which is at (-b/2a , y)

-b/2a would be 2/2 = 1 ... so find the y value at x = 1

12 - 2(1) - 15 = 1-17 = -16

So the vertex is at (1,-16)

Since the parabola opens upward from that point the minimum value of the range is y = -16

The range would include the point -16 so it is actually

R = [-16,infinity)