2 classes of 21 students each
21 × 2 classes = 42 students in total
42 × 3 mins = 126 minutes for 42 students
10 mins for 2 class pics = 20 minutes
126 + 20 = 146 minutes = 2 hours and 26 minutes
It should take 146 minutes (2 hours and 26 minutes) to take all the pictures.
Answer:
- t = 1.5; it takes 1.5 seconds to reach the maximum height and 3 seconds to fall back to the ground.
Explanation:
<u>1) Explanation of the model:</u>
- Given: h(t) = -16t² + 48t
- This is a quadratic function, so the height is modeled by a patabola.
- This means that it has a vertex which is the minimum or maximu, height. Since the coefficient of the leading (quadratic) term is negative, the parabola opens downward and the vertex is the maximum height of the soccer ball.
<u>2) Axis of symmetry:</u>
- The axis of symmetry of a parabola is the vertical line that passes through the vertex.
- In the general form of the parabola, ax² + bx + c, the axis of symmetry is given by x = -b/(2a)
- In our model a = - 16, and b = 48, so you get: t = - ( 48) / ( 2 × (-16) ) = 1.5
<u>Conclusion</u>: since t = 1.5 is the axys of symmetry, it means that at t = 1.5 the ball reachs its maximum height and that it will take the same additional time to fall back to the ground, whic is a tolal of 1. 5 s + 1.5 s = 3.0 s.
Answer: t = 1.5; it takes 1.5 seconds to reach the maximum height and 3 seconds to fall back to the ground.