Jayne stopped to get gas before going on a road trip. The tank already had 4 gallons of gas in it. Which equation relates the total amount of gasoline in the tank, [tex]y[/tex], to the number of gallons that she put in the tank, [tex]x[/tex]?

A. [tex]y = 4 + x[/tex]
B. [tex]y = x - 4[/tex]
C. [tex]y = 4 \cdot x[/tex]
D. [tex]y = x + 4[/tex]



Answer :

Let's go through the problem step by step to find out the correct equation that relates the total amount of gasoline in the tank, [tex]\( y \)[/tex], to the number of gallons that Jayne put in the tank, [tex]\( x \)[/tex].

1. Analyze the Initial Condition:
- The tank already had 4 gallons of gas in it. This means before Jayne puts any additional gas in, there are already 4 gallons in the tank.

2. Account for the Additional Gasoline:
- Let's denote the gasoline that Jayne adds to the tank as [tex]\( x \)[/tex].

3. Relate the Total Amount of Gasoline:
- The total amount of gasoline [tex]\( y \)[/tex] in the tank is the sum of the initial amount of gasoline (which is 4 gallons) and the additional gasoline [tex]\( x \)[/tex] that Jayne puts in.

4. Formulate the Equation:
- Given that the total amount, [tex]\( y \)[/tex], is the sum of the initial 4 gallons and [tex]\( x \)[/tex], we can write:
[tex]\[ y = 4 + x \][/tex]

Therefore, the equation that correctly relates the total amount of gasoline in the tank, [tex]\( y \)[/tex], to the number of gallons that Jayne put in the tank, [tex]\( x \)[/tex], is:
[tex]\[ y = 4 + x \][/tex]

Thus, the correct choice is:
[tex]\[ \boxed{y = 4 + x} \][/tex]