Page 45 - Math Course 3 (Book 1)

Quadratic Equations

Graph Opens Downward Your Turn!

Examples Graph Opens Upwards

2
Use a table of values to graph y = x + 2x + 3.
ARCHERY
2
The equation y = –x + 6x + 4 represents the height
y of an arrow x seconds after it is shot into the area. A. B.
2
Use a table of values to graph y = –x + 6x + 4.
Graph these ordered pairs and connect them with a
smooth curve.

Answer

x y
C. D.
–2 –12
–1 –3

0 4
1 9
2 12

3 13 x y
4 12 Answer –3 6

5 9 –2 3
–1 2
0 3
2
The equation y = –x + 6x + 4 represents the height
y of an arrow x seconds after it is shot into the 1 6
area. What are the mathematical domain and range
of the function? Graph Opens Downward

2
Use a table of values to graph y = –x + 4.
domain: all real numbers;
Answer A. C.
range: {y | y ≤ 13}

2
The equation y = –x + 6x + 4 represents the
height y of an arrow x seconds after it is shot into
the area. Describe reasonable domain and range
values for this situation. B. D.

The arrow is in the air for about
6.6 seconds, so a reasonable
domain is D: {x | 0 < x < 6.6}.
Answer
The height of the arrow ranges
from 0 to 13 feet, so a reasonable
range is R: {y | 0 < y < 13}.

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