When running a 100-meter race Usain Bolt reached his top speed when he was 55 meters from the starting line and had been running for 4.6 seconds since the start of the race. He passed the 80 meter line of the race when he had been running for 7.8 seconds since the start of the race. Let
t
represent the number of seconds since the start of the race.

Let
d
represent Usain's distance from the starting line of the race.

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.

(0.2)+(-8)=0.3+-3+0.3m is the equation i guess? ?

step-by-step explanation:

b

step-by-step explanation: