Askydiver jumps from a plane from an altitude of 6000 feet and observer on the ground make sure the skydivers altitude at time t =0 to the 4500 feet the linear graph shows the skydivers altitude at various times during her descent

The y - intercept is where the line cuts the y- axis... or vertical axis. this is her height when the observer first sees her

pick 2 points on the line and find the slope

say (0, 4500) and (1, 3000)

slope = change in altitude/change in time
= (3000 - 45000)/(1 - 0)

the x intercept is where the line cuts the x-axis.. horizontal axis

it shows the time it took the skydiver to travel from 4500 feet to the ground.

Hope it helps