Download 1 - Homework Market

1. Solve the problem.
A ball is kicked upward with an initial velocity of 52 feet per second. The ball's
height, h (in feet), from the ground is modeled by
, where t is
measured in seconds. How much time does the ball take to reach its highest
point? What is its height at this point?
a. 1.625 sec; 84.5 ft
c. 3.25 sec; 42.25 ft
b. 1.625 sec; 42.25 ft
d. 3.25 sec; 126.75 ft
2. Make a scatter plot of the data below.
x
25
50
75
100
125
150
175
y
150
178
216
265
323
392
470.4
Use the quadratic regression feature of a graphing calculator to find a quadratic
model. Round to the nearest thousdandths place.
a.
b.
c.
d.
3. What is the value of c in the given quadratic regression equation?
a. 1
b. -0.19
c. 1.23
d. 0
4.
The data set represents a month-to-month progression of gasoline prices over
the course of several months in an unspecified city. Use a graphing calculator to
determine the quadratic regression equation for this data set.
x
y
a.
b.
0
1
2
3
4
5
1.30 1.34 1.38 2.20 2.88 2.24
c.
d.
5.
Solve the problem.
A ball is kicked upward with an initial velocity of 68 feet per second. The ball's
height, h (in feet), from the ground is modeled by
, where t is
measured in seconds. How much time does the ball take to reach its highest
point? What is its height at this point?
a. 4.25 sec; 72.25 ft
c. 2.125 sec; 144.5 ft
b. 4.25 sec; 216.75 ft
d. 2.125 sec; 72.25 ft
6.
The Air Quality Index, or AQI, measures how polluted the air is in your city and
assigns a number based on the quality of the air. Over 100 is "Unhealthy".
The following quadratic regression equation, models the AQI over time, where n
represents the number of days the AQI exceeded 100, and t represents the
number of years since 1990.
Estimate the number of days the AQI exceeded 100 in the year 2002. Round to the
nearest whole day. (Hint: t = 0 corresponds to the year 1990.)
a.
b.
c.
d.
281 days
97 days
135 days
52 days
7,
Solve the problem.
A ball is kicked upward with an initial velocity of 68 feet per second. The ball's
height, h (in feet), from the ground is modeled by
, where t is
measured in seconds. What is the practical domain in this situation?
a.
c. All real numbers
b.
d.
8.
Fill in the blank by choosing the most appropriate word.
Regression equations are usually used to predict values of unavailable data. If
the data do not closely model a particular type of function, then that type of
function is not appropriate to use in statistical regression. The more closely data
fit a model, the more _______________ predicted values will be.
accurate
a.
b.
quadratic
scattered
c.
d.
variable
9.
Suppose that a water fountain produces a stream of water that follows the shape
of a parabola. Assigning the origin of a coordinate system to the point where the
water stream emerges from the fountain, a measurement shows that the
maximum height of the stream occurs at the point (6, 5). Use symmetry to
identify a third point and find a quadratic regression equation for the stream of
water.
a.
c.
b.
d.
The data set represents a month-to-month progression of gasoline prices over
the course of several months in an unspecified city. Use a graphing calculator to
determine the quadratic regression equation for this data set.
x
y
a.
b.
0
1
2
3
4
5
3.29
2.88
2.82
3.46 3.33
2.24
c.
d.