The formula for speed is the total distance traveled over time. We shall calculate the 2 speeds individually- before and after lunch. Afterwhich, we shall add them together and divide by 2 to get the average. Before lunch s = 132 mi / 3 hr = 44 mi/hr After lunch s = 240 mi / 5 hr = 48 mi/hr
The zero of a function is the x-value at which the function value is zero. That is, the value of the function that intersects the x-axis. From the picture, the zero is -5