Question

The amount of freshwater left in the tanks of a 19th century clipper ship is a linear function of the time since the ship left port, as shown in the table. Write an equation in point-slope form that represents the function. Then find the amount of water that will be left in the ship's tanks 50 days after leaving port. This is the table below.
time      amount
(days)    (gal)
1            3555
8            3240
15          2925

Answer 1

First solve the slope, mm = ( y1 - y2 ) / ( x1 - x2 )m = ( 3555 - 3240 ) / ( 1 - 8 ) m = - 45 gal / day
then solve the y intercept, by = mx + b
3555 = (-45)(1) + b3555 = -45 + bb = 3555 + 45b = 3600
so day 50
y = -45x + 3600y = -45(50) + 3600y = 1350 gal