B im almost 100% sure, the 3 is where it starts on the Y axis so its based off the 2x which goes up 2 over to the right one, if it goes on a downward slope like the bottom two then that means its a negative equation.
You can calculate the area of the whole pizza according to the formula: S=1/2*π*r². And the area of 8 piece is 1/8S while the area of 12 piece is 1/12S. The answer should be 1/8S-1/12S=4/3π.
