Question

The domain of function
f
(
x
)
is the set of all integers from 0 to 15, and the range of
f
(
x
)
is the set of all multiples of 5 from 0 to 75.

Which of the following statements are true? Select THREE that apply.

The point
(
5
,

1
)
could be on the graph of
f
(
x
)
.


The point
(
7
,

15
)
could be on the graph of
f
(
x
)
.


The point
(
20
,

10
)
could be on the graph of
f
(
x
)
.


The statement
f
(
0
)
=
0
could apply to
f
(
x
)
.


The statement
f
(
10
)
=
75
could apply to
f
(
x
)
.


The statement
f
(
15
)
=
100
could apply to
f
(
x
)
.

Answer 1

True: The point (7, 15); the statement f(0) = 0; and the statement f(10) = 75.

Reason: x must be an integer 0–15 and f(x) must be a multiple of 5 between 0 and 75. (7,15) meets both, f(0)=0 meets both, and f(10)=75 meets both. The others fail because y=1 is not a multiple of 5, x=20 is outside the domain, and 100 is greater than the maximum range value 75.