Answer: the rate at which the distance between the boats is increasing is 68 mph
Step-by-step explanation:
The direction of movement of both boats forms a right angle triangle. The distance travelled due south and due east by both boats represents the legs of the triangle. Their distance apart after t hours represents the hypotenuse of the right angle triangle.
Let x represent the length the shorter leg(south) of the right angle triangle.
Let y represent the length the longer leg(east) of the right angle triangle.
Let z represent the hypotenuse.
Applying Pythagoras theorem
Hypotenuse² = opposite side² + adjacent side²
Therefore
z² = x² + y²
To determine the rate at which the distances are changing, we would differentiate with respect to t. It becomes
2zdz/dt = 2xdx/dt + 2ydy/dt- - - -- - -1
One travels south at 32 mi/h and the other travels east at 60 mi/h. It means that
dx/dt = 32
dy/dt = 60
Distance = speed × time
Since t = 0.5 hour, then
x = 32 × 0.5 = 16 miles
y = 60 × 0.5 = 30 miles
z² = 16² + 30² = 256 + 900
z = √1156
z = 34 miles
Substituting these values into equation 1, it becomes
2 × 34 × dz/dt = (2 × 16 × 32) + 2 × 30 × 60
68dz/dt = 1024 + 3600
68dz/dt = 4624
dz/dt = 4624/68
dz/dt = 68 mph
|k - 2| * |3k| - 1
Substitute all of the "k" variables for -4
|-4 - 2| * |3(-4)| - 1
Multiply 3 by -4
|-4 - 2| * |-12| -1
Subtract 2 from -4
|-6| * |-12| - 1
Use the absolute value method
6 * 12 - 1
Combine like terms
Final Answer: 71
Answer:
C~7
Step-by-step explanation:
Answer:
1) incorrect
2) incorrect
Step-by-step explanation:
-2x-2x = 0 ?
-2x -2x = -4x
It will be 0 only if x = 0.
Not always true, so incorrect
x+x = x² ?
2x = x²
They will be equal if x = 0 or 2.
Not always true so incorrect
9(-6x-2)-7(-10x-2)
Simplify, by distributing the 9 and the -7
-54x-18+70x+14
Combine like terms
16x-4 is the simplified expression
Hope this helped!
