Question

Which of the following functions could model the amount of gallons of water, ƒ(x), that the bathtub will contain after x minutes of being filled?

A
ƒ(x) = 5x + 7

B
ƒ(x) = 5x + 12

C
ƒ(x) = 7x + 5

D
ƒ(x) = 12x + 5

Answer 1

Explanation:

It’s 5x+7 A on here and C on there

Answer 2

• A . ƒ(x) = 5x + 7

Explanation:

As per table we have

• Common difference of 5 (bottom row)
• So initial amount of water is 12 - 5 = 7 gallons

So the function is:

• f(x) = 5x + 7

Correct option is A