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Course: Algebra 2 (FL B.E.S.T.) > Unit 3

Lesson 5: Interpreting quadratic models
Math
Algebra 2 (FL B.E.S.T.)
Quadratic functions & equations introduction
Interpreting quadratic models
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Interpret quadratic models

Google Classroom

Problem

Amir throws a stone off of a bridge into a river. The stone's height (in meters above the water) t seconds after Amir throws it is modeled by
h(t)=−5t2+20t+160
Amir wants to know when the stone will reach its highest point.
1) Rewrite the function in a different form (factored or vertex) where the answer appears as a number in the equation.
h(t)=
2) How many seconds after being thrown did the stone reach its highest point?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
seconds