y intercept when x = 0
A dolphin is 42 feet underwater means at x = 0 y = -42
so y intercept (0,-42)
x intercept when y = 0
ascends at a constant rate for 16 seconds until it reaches the surface
means x = 16 and y = 0
so x intercept (16,0)
slope = (y2 - y1) / (x2 - x1)
slope = 42/16 = 2.625
so equation in slope intercept is y = 2.625x - 42
hope it helps
