Posted by hannah on Tuesday, January 14, 2014 at 12:32pm.
Stephanie is working on a graph that represents the path of a roller coaster. The point (0, 840) represents the point at which the roller coaster first begins to drop at a constant rate. The point (15, 240) represents a point along the ride at which the roller coaster is still dropping. If the xintercept represents the point at which the ride stops dropping, what is the xintercept?

math  Steve, Tuesday, January 14, 2014 at 12:37pm
since y decreased by 600 when x increased by 15,
y = 840  40x
now solve for x when y=0