Anyone can Answer 20x + 40 = 80 clear x please

Can someone with this one pre-calc question? the finishing time for a runner completing the 200-meter dash is affected by the tail-wind speed, s. the change, t, in a runner's performance is modeled by the function shown below: t= 0.0119s^2 - 0.308s - 0.0003 predict the change in a runner's finishing time with a wind speed of 3 meters/second. note: a negative answer means the runner finishes with a lower time. round to the nearest hundredth.

Aword processing program requires a 7- digit registration code made up of the digits 1,2,4,5,6,7 and 9 each number has to be used and no number can be used mor than once how many codes are possible

Last week jason walked 3 1/4 miles each day for 3 days and 4 5/8 miles each day for 4 days. about how many miles did jason walk last week?