Question

5. Suppose the stacks of cases of bottled water on the shelves of a major grocery store follow
the graph of the equation 4r + y= 36 where r is hours after the store opens and y is the
number of cases on the shelves. All of the water is sold. What is the domain of the
variable x?
© (0,6]
® (0,91
© (0,12]
© (-2,91​

Answer 1

ANSWER

C [0,9]

EXPLANATION

The number of bottled water on the shelf is modeled by the function

$4x + y = 36$

We make y the subject to obtain;

$y = 36 - 4x$

When no water is sold, then x=0.

When all the bottles are sold, then

$4x - 36 = 0$

$4x = 36$

$x = \frac{36}{4} = 9$

Therefore the store cannot sell more than 9 bottles.

The domain is [0,9]