Answer:13 miles over the speed limit
Step-by-step explanation:
Answer:
B
the middle one
Step-by-step explanation:
R = speed in still water
r + c = speed with current
r - c = speed against current
3.5(r + c) = 70
r + c = 20
c = 20 - r
4(r + c) = distance from pier to pier
5(r - c) = distance from pier to pier
4(r + c) = 5(r - c)
4(r + 20 - r) = 5(r - 20 + r)
80 = 10r - 100
180 = 10r
18 = r
The speed in still water is 18 km/hour
The answer is the first option: it has the same domain as the function f(x) = - √(-x).
The domain is the set of x-values for which the function is defined.
The square root function is defined only for zero and positve values.
- x is positive when x negative.
So the domain for - √(-x) and √(-x) are the same: x less than or equal to zero.
