The function f(t) = t2 + 6t − 20 represents a parabola.

part a: rewrite the function in vertex form by completing the square. show your work. (6 points)

part b: determine the vertex and indicate whether it is a maximum or a minimum on the graph. how do you know? (2 points)
the function h(t) = −16t2 + 90t + 50 shows the height h(t), in feet, of a projectile after t seconds. a second object moves in the air along a path represented by g(t) = 28 + 48.8t, where g(t) is the height, in feet, of the object from the ground at time t seconds.

part a: create a table using integers 1 through 4 for the 2 functions. between what 2 seconds is the solution to h(t) = g(t) located? how do you know? (6 points)

part b: explain what the solution from part a means in the context of the problem. (4 points)

Part A: f(t) = t² + 6t - 20
              u = t² + 6t - 20
         + 20            + 20
      u + 20 = t² + 6t
u + 20 + 9 = t² + 6t + 9
      u + 29 = t² + 3t + 3t + 9
      u + 29 = t(t) + t(3) + 3(t) + 3(3)
      u + 29 = t(t + 3) + 3(t + 3)
      u + 29 = (t + 3)(t + 3)
      u + 29 = (t + 3)²
          - 29       - 29
              u = (t + 3)² - 29

Part B: The vertex is (-3, -29). The graph shows that it is a minimum because it shows that there is a positive sign before the x²-term, making the parabola open up and has a minimum vertex of (-3, -29).

Part A: g(t) = 48.8t + 28           h(t) = -16t² + 90t + 50
            | t |   g(t)  |                          |  t  |  h(t)  |
            |-4|-167.2|                          | -4 | -566 |
            |-3|-118.4|                          | -3 | -364 |
            |-2| -69.6 |                          | -2 | -194 |
            |-1| -20.8 |                          | -1 |  -56  |
            |0 |   -28  |                          |  0  |   50  |
            |1 |  76.8 |                          |  1  |  124 |
            |2 | 125.6|                          |  2  | 166  |
            |3 | 174.4|                          |  3  | 176  |
            |4 | 223.2|                          |  4  | 154  |
The two seconds that the solution of g(t) and h(t) is located is between -1 and 4 seconds because it shows that they have two solutions, making it between -1 and 4 seconds.

Part B: The solution from Part A means that you have to find two solutions in order to know where the solutions of the two functions are located at.