Question

the cost of gasoline is $4 per gallon.
y = ?x
complete the direct variation to relate
cost and gallons of gas.

Explanation:

Step1: Define variables

Let \( x \) be the number of gallons of gas, and \( y \) be the cost (in dollars) of the gas.

Step2: Recall direct variation formula

Direct variation is of the form \( y = kx \), where \( k \) is the constant of variation (rate).

Step3: Determine the constant \( k \)

The cost per gallon is $4, so for each gallon (LXI0), the cost LXI1 increases by $4. Thus, \( k = 4 \).

Answer:

\( y = 4x \), so the value in the box is \( 4 \).