Answer:
-5xa^2-7a^3+7a^2+4
Step-by-step explanation:
Let each side perpendicular to the river be "x".Then the side parallel to the river is "400-2x".
The formula for Area = width*length
A(x) = x(400-2x)
A(x) = 400x - 2x^2
You have a quadratic with a = -2 and b = 400
Maximum Area occurs where x = -b/2a = -400/(2*-2) = 100 ft. (width)
length = 400-2x = 400-2*100 = 200 ft (length)
Answer:
it is true.
Step-by-step explanation:
the proportions 4:6 and 10:15 can both be simplified into 2/3.
hope this helped! :)
I think it is 8.83? I am not positive but it is worth a try
Given:
unit rate: 20km/h
Speed = distance / time
20kmh = 30km / time
time = 20kmh / 30km
time = 2/3 hrs or 40 minutes
2/3 hrs * 60mins/hr = (2*60)/3 = 120/3 = 40 minutes