Quadratic word problems, and choosing a method

Answer Key - Grade 9 Math Worksheet

Circle the best answer, or write your answer on the line.

1. 1.

   Esme tosses a play ball up from 5 feet at 40 feet per second. Its height is h = -16t² + 40t + 5. When does it land, in seconds to the nearest tenth?

   2.6
2. 2.

   Jun throws a basketball up from 4 feet at 48 feet per second. Its height is h = -16t² + 48t + 4. When does it land, in seconds to the nearest tenth?

   3.1
3. 3.

   Luz tosses a play ball gently up from 5 feet at 24 feet per second. Its height is h = -16t² + 24t + 5. When does it land, in seconds to the nearest tenth?

   1.7
4. 4.

   Noah's rug is 3 feet longer than it is wide and covers 40 square feet. Let x be the width, so x(x + 3) = 40. What is the width?

   5
5. 5.

   Pia's poster is 6 inches taller than it is wide, with an area of 432 square inches. Let x be the width, so x(x + 6) = 432. What is the width?

   18
6. 6.

   Ren's school banner is 7 feet longer than it is wide, with an area of 44 square feet. Let x be the width, so x(x + 7) = 44. What is the width?

   4
7. 7.

   Tala opens a book to two facing pages. The page numbers multiply to 156. Call the smaller number n, so n(n + 1) = 156. What is the smaller number?

   12
8. 8.

   Zee picks two consecutive even numbers that multiply to 224. Call the smaller number n, so n(n + 2) = 224. What is the smaller number?

   14
9. 9.

   Ari picks two consecutive odd numbers that multiply to 255. Call the smaller number n, so n(n + 2) = 255. What is the smaller number?

   15
10. 10.

    Bo's robot thinks of two consecutive whole numbers that multiply to 306. Call the smaller number n, so n(n + 1) = 306. What is the smaller number?

    17