Interpreting Solutions to Functions

Is this table a function?  Explain.

• Yes, because none of the inputs repeat.

• Yes, because the inputs repeat but have the same output

• No because the inputs repeat

• No because the inputs repeat and have different outputs

Is the graph a function?  Explain.

• Yes, because if I draw a vertical line, it only crosses once.

• No because if I draw a vertical line, it crosses more than once

• Yes because it does not go into the negative numbers

• No because it's not a straight line

What is the domain of this function?

• All real numbers

• All real number bigger than 0

• All real number bigger than or equal to 0

• All real numbers less than 0

What is the domain of the function?

• All real numbers

• All real numbers greater than -3

• All real number less than -3

• All real numbers except -3

Derek works at Subway making $9.25 an hour.  The function d(x)=9.25x tells us how much money Derek makes after x hours of working.  What is the meaning of d(4)=37?

• After 4 hours of work, Derek makes $37.

• Derek needs $4 more to have $37 total.

• After working for 4 days, Derek makes $37 total.

• After 4 hours of work, Derek now makes $37 an hour instead of $9.25.

Consider the function t(x)=x/8+2x.  Find t(16).

• 34

• 160

• 16

• 56

A company is selling bubble gum.  The function g(x)=3x+4 tells the company how much to charge if someone buys x packages of bubble gum.  Find g(8) and tell what it means within the context of the problem.

• g(8)=8.  This means that after 8 packages of gum, the company makes $8.

• g(8)=42.  This means that 8 packages of gum costs $42.

• g(8)=28.  This means that 8 packages of gum costs $28.

• g(8)=24.  This means that 8 packages of gum costs $24.

Consider the function k(x)=x/5-3.  Find k(-20).

• -20

• 1

• -7

• -1

What is happening in the graph between 30 and 40 minutes?

• Sarah is accelerating

• Sarah is not moving

• Sarah is slowing down

• Sarah is travelling at a constant speed

Find the y-intercept(s) of the graph shown.

• (-3.3, 0)

• (5.6, 0)

• (-5, 0)

• (0, 4)