Question

module 3 test
name decmel 3004

1. what is the domain of the relation shown in the graph?

o {1, 5}
o {-3, -1, 1, 5}
o {-5, -4, -2, 0, 3}
o {-5, -4, -3, -2, -1, 0, 1, 3, 5}

1. which describes the scale on the x - and y - axes that is most appropriate for the graph of (25, 10), (50, 15), (-37.5, -20), (125, 25), and (75, 30)?

o both the x - and y - axes should extend from - 100 to 100 with a scale of 1.
o the x - axis should extend from - 50 to 150 with a scale of 25. the y - axis should extend from - 30 to 30 with a scale of 10.
o both the x - and y - axes should extend from - 200 to 200 with a scale of 100.
o the x - axis should extend from - 10 to 10 with a scale of 1. the y - axis should extend from - 30 to 30 with a scale of 20.

1. is each relationship a function? circle yes or no.

a. yes no
b. yes no
c. yes no
d. yes no

Explanation:

1.

Step1: Recall domain definition

The domain of a relation is the set of all x - values of the ordered - pairs in the relation. Looking at the graph, the x - values of the points are - 3, - 1, 1, 5.

Step1: Find min and max x - values

The x - values of the points are 25, 50, - 37.5, 125, 75. The minimum x - value is approximately - 37.5 and the maximum is 125. A scale of 25 for the x - axis from - 50 to 150 would cover these values well.

Step2: Find min and max y - values

The y - values of the points are 10, 15, - 20, 25, 30. The minimum y - value is - 20 and the maximum is 30. A scale of 10 for the y - axis from - 30 to 30 would cover these values well.

Step1: Check relation A

In relation A, each x - value is paired with exactly one y - value, so it is a function.

Step2: Check relation B

In relation B, each x - value in the domain is paired with exactly one y - value in the range, so it is a function.

Step3: Check relation C

The graph of relation C fails the vertical - line test (a vertical line can intersect the graph at more than one point), so it is not a function.

Step4: Check relation D

In relation D, each x - value in the set of ordered pairs is paired with exactly one y - value, so it is a function.

Answer:

{-3, -1, 1, 5}

2.