Jason jumps from a plane at an altitude of 1000 m. his parachute opens after 10 seconds. the graph shows the relationship between the distance traveled and time. how far does he fall in 1 minute and 20 seconds? continuous graph with the y axis labeled distance (m) and the x axis labeled time, min. the function consists of 3 lines, the first is almost vertical with a positive slope connecting the points 0,0, to approximately 1 of 6, 250. from that point the second line connects to the first and passes through the points 1,500, 2,800 and 2 1 over 3, 1000. from that point the function is horizontal.

600 m

The slope between 1 minute and 2 minutes is ...

... (800 -500)/(2 -1) = 300 . . . . . . m/min

Thus in 20 seconds, 1/3 minute, Jason will fall ...

... (1/3 min)·(300 m/min) = 100 m

This distance is in addition to the 500 m he has already fallen in the first minute.

In 1 min 20 sec, Jason falls 500 m + 100 m = 600 m.

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Comment on the graph

We don't expect Jason's rate of fall to change dramatically at the 2-minute mark. We suspect the last point should be (2 2/3, 1000).

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this