21
QuizMultiple Choice

Strength of Correlation — Cumulative exam

Question 21 • High School Math 2 A

The quadratic model f(x) = –5x2 + 200 represents the approximate height, in meters, of a ball x seconds after being dropped. The ball is 50 meters from the ground after about how many seconds?

Answer
A
2.45
B
3.16
C
5.48
D
7.07

Explanation

Set the height equal to 50 meters: −5x² + 200 = 50. Subtract 200 and divide by −5 to get x² = 30, so x = √30 ≈ 5.48 seconds (taking the positive time). The correct choice is 5.48 seconds.

AI-written and checked against the verified answer.

Previous
Next