Answer:
Expression: Y = -10/3 X
Y = 10/3
Step-by-step explanation:
If Y varies directly as X, then;
Y∝X
Y = kX
k is the constant of variation
If Y = 10 and X = -3
10 = -3k
k = -10/3
Substitute k = -10/3 into the expression Y = kX
Y = -10/3 X
This gives the required expression
To get the value of Y when X = -1
Recall that Y = kX
Y = -10/3 (-1)
Y = 10/3
Hence the value of Y is 10/3
Answer:
4 stations
Step-by-step explanation:
If we need to be at least 98% certain that an enemy plane flying over will be detected by at least one station, we must ensure that there is at most a 2% chance that no radar stations detect the plane.
The probability that a single radar station does not detect the plane is 0.35.
For n radar stations:

Rounding up to the next whole station, at least 4 stations are needed.
Answer:
Step-by-step explanation:
x^3-2y^2-3x^3+z^4
(3)^3-2(5)^3+(-3)^4
-142