AnswersFL-1200330-Algebra 2 CRModeling with Quadratic Equations

Modeling with Quadratic Equations Answers

3 verified answers2 views
3

Carmen is using the quadratic equation (x + 15)(x) = 100 where x represents the width of a picture frame. Which statement about the solutions x = 5 and x = –20 is true?

A
The solutions x = 5 and x = –20 are reasonable.
B
The solution x = 5 should be kept, but x = –20 is unreasonable.
C
The solution x = –20 should be kept, but x = 5 is unreasonable.
D
The solutions x = 5 and x = –20 are unreasonable.
4

Two children are throwing a baseball back and forth. The ball is 4 ft above the ground when it leaves one child’s hand with an upward velocity of 36 ft/s. If acceleration due to gravity is –16 ft/s2, how high above the ground is the ball 2 s after it is thrown?h(t) = at2 + vt + h0

A
12 ft
B
20 ft
C
76 ft
D
116 ft
5

The total area of two square windows is 1,025 in.2. Each side of the larger window is 5 in. longer than the sides of the smaller window. How long are the sides of the smaller window?A = s2

A
13.5 in.
B
20 in.
C
25 in.
D
31.6 in.
6

A softball pitcher tosses a ball straight upward from a height of 3 feet above the ground with an initial velocity of 50 feet per second. The acceleration due to gravity is –16 ft/s².Which quadratic equation represents the height of the ball above the ground after t seconds?h(t) = at2 + vt + h0

A
h(t) = 50t2 – 16t + 3
B
h(t) = –16t2 + 50t + 3
C
3 = –16t2 + 50t + h0
D
3 = 50t2 – 16t + h0
7

A projectile is launched straight up from the ground with an initial velocity of 120 ft/s. If acceleration due to gravity is –16 ft/s2, after about how many seconds will the object reach a height of 200 ft?h(t) = at2 + vt + h0

A
1.0 s
B
1.7 s
C
2.5 s
D
8.0 s
8

The Davidson family wants to expand its rectangular patio, which currently measures 15 ft by 12 ft. They want to extend the length and width the same amount to increase the total area of the patio by 160 ft2. Which quadratic equation best models the situation?A = lw

A
(15)(12) + (x)(x) = (15)(12) + 160
B
(15x)(12x) = (15)(12) + 160
C
2(15 + x) + 2(12 + x) = (15)(12) + 160
D
(15 + x)(12 + x) = (15)(12) + 160
9

A quarterback throws an incomplete pass. The height of the football at time t is modeled by the equation h(t) = –16t2 + 40t + 7. Rounded to the nearest tenth, the solutions to the equation when h(t) = 0 feet are –0.2 s and 2.7 s. Which solution can be eliminated and why?

A
The solution –0.2 s can be eliminated because time cannot be a negative value.
B
The solution –0.2 s can be eliminated because the pass was not thrown backward.
C
The solution 2.7 s can be eliminated because the pass was thrown backward.
D
The solution 2.7 s can be eliminated because a ball cannot be in the air for that long due to gravity.
10

A skydiver jumps from an airplane at an altitude of 2,500 ft. He falls under the force of gravity until he opens his parachute at an altitude of 1,000 ft. Using the initial velocity of zero, approximately how long does the jumper fall before he opens his chute?For this quadratic model we will let the y-axis be the axis of symmetry.h(t) = -16t2 + vt + h0

A
2.4 s
B
9.7 s
C
12.5 s
D
14.8 s
11

When using a quadratic equation in the form y = ax2 + bx + c to model the height of a projectile (y) over time (x), which of the following is always represented by the constant term?

A
the initial height of the projectile
B
the initial velocity of the projectile
C
the time at which the projectile hits the ground
D
the maximum height of the projectile
12

A firework is launched into the air from ground level with an initial velocity of 128 ft/s. If acceleration due to gravity is –16 ft/s2, what is the maximum height reached by the firework?h(t) = at2 + vt + h0

A
256 ft
B
448 ft
C
512 ft
D
1,024 ft
13

The owner of an office building is expanding the length and width of a parking lot by the same amount. The lot currently measures 120 ft by 80 ft, and the expansion will increase its area by 4,400 ft2. By how many feet should the length of the parking lot be increased?A = lw

A
1.2 ft
B
20 ft
C
66.3 ft
D
220 ft

Did you find these answers helpful?