The diameter is 20 so the radius is 10.
A=<span>πr^2
A=</span>π10^2
A=100π
C=2πr
C=2π10
C=20π
Plug in random values for x and find y value
assume x = 10 then y = 430
Express as ordered pair:(10,430)
Answer:
20ln(3)
Step-by-step explanation:
Put 15 for A and solve for t.
15 = 45e^(-.05t)
15/45 = 1/3 = e^(-.05t) . . . . divide by 45
ln(1/3) = -.05t . . . . . . . . . . . take natural logs
20ln(3) = t . . . . . . . . . . . . . . multiply by 20, simplify
It will take 20·ln(3) years for the area to decrease to 15 km^2.
The answer is a 40% discount because it costs $24 less than the original price and 24 divided by 60 is .4 or 40%!
