Step-by-step explanation: First you have to know how much it drills per hour. For that your ganna have to divide -72 and 24 to get answer of how much per hour, which is -3 per hour. Finally, your ganna have to multiply -3 and 15 which gives you the final answer of -45 feet in 15 hours
First, we need to find out the rate at which the machine was digging. To do this, we need to divide -72 by 24, to find how many feet are dug each day. Once we divide, we get a rate of -3 feet per hour. We can then make an equation based on this, y = -3x. We can then plug in the hours we want to find, 15, into the equation, to make y = -3(15). Once we multiply, we get y = -45, so our answer is -45 feet.
