Page 54 - Math Course 3 (Book 1)

Quadratic Equations: Graphing

Real World Example

GOLF
Martin hits a golf ball with an upward velocity of 120 Answer
2
feet per second. The function y = –16t + 120t models
the flight of the golf ball, hit at ground level, where y is
the height of the ball in feet after t seconds. How long
was the golf ball in the air?

A. between 7 and 8 seconds
B. between 6 and 7 seconds
C. between 8 and 9 seconds
D. between 0 and 1 second

Skill Practice!

Solve each equation by graphing.

2
2
1. x – 2x + 3 = 0 2. c + 6c + 8 = 0

3. a – 2a = –1 4. n –7n = –10
2
2

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