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5 The amount of fuel in a car's tank, V, in litres, can be modelled by a linear function, V = mx + c where is the distance driven measured in kilometres. After driving 100 km, the amount of fuel in the tank is 33 litres. (a) Write down an equation that describes this information . After driving 250 km, the amount of fuel in the tank is 22.5 litres . (b) Write down an equation that describes this second piece of information . () Calculate the amount of fuel in the tank after driving 50 km.

User Jaeyong
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The linear function that models the fuel in the car's tank based on distance driven is V = -0.07x + 40, derived from the provided data points. After driving 50 km, the car would have 36.5 litres of fuel remaining in the tank.

Step-by-step explanation:

The linear equation that models the amount of fuel, V, in litres in a car's tank as a function of the distance driven, x, in kilometres is V = mx + c. Given that after driving 100 km, the fuel in the tank is 33 litres, we can form the equation 33 = m(100) + c. After driving 250 km, the amount of fuel is 22.5 litres, resulting in the equation 22.5 = m(250) + c.

To find the values of m and c, we solve this system of equations. Subtracting the first equation from the second gives a new equation -10.5 = 150m. Solving for m, we find that m = -0.07. Using this value in the first equation, we find 33 = -0.07(100) + c, which gives c = 40. Now, the complete equation is V = -0.07x + 40.

To calculate the amount of fuel in the tank after driving 50 km, we substitute x = 50 into the equation: V = -0.07(50) + 40. This results in V = 36.5 litres.

User BastianW
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