Answer:
-390 mph
Step-by-step explanation:
Let a and b represent, respectively, the distances of A and B from the airport. The distance d between the planes is then given by the Pythagorean theorem as ...
d² = a² + b²
Differentiating with respect to time, we have ...
2d·d' = 2a·a' +2b·b'
Solving for d', we get ...
d' = (a/d)a' +(b/d)b'
The value of d at the time of interest is ...
d = √(a² +b²) = √(30² +40²) = √2500 = 50
Then the rate of change of separation is ...
d' = (30/50)(-250 mph) +(40/50)(-300 mph) = (-150 -240) mph
d' = -390 mph
The distance between planes is decreasing at 390 miles per hour.
Answer: 6
Explanation: The EXACT calculation would be 5.9215.. so the closest approximation would be
6, as it's only about .08 -ish away from 6.
Answer:
EF=20
Step-by-step explanation:
EF is midsegment of the triangle so the equation is
AB/2=EF
7x-2/2=2x+8
7x-2=4x+16
7x-4x=16+2
3x=18
x=18/3
x=6
EF=2×6+8
=12+8
=20