two bicycle riders start from the same point and ride in opposite directions. one rider is moving twice as the other. in 3 hours, they are 72 miles apart. find the rate of each rider.​

Step-by-step explanation:

let X = speed of slow bicycle rider

2x=speed of fast bicycle rider

3(x+2x)=72

X=8mph(slowest bicycle rider)

2x=16mph(fastest bicycle rider)

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

answer:

f(5/2) = 10/3

i hope this you!

you didn't post any answer choices, so its not 100% clear what your teacher is looking for

however, log(15/7) is equivalent to log(15) - log(7)

i'm using the rule log(x/y) = log(x) - log(y)