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
Let,
- Mass of the steel be 108x
- Mass of the copper be 7x
- Then, Total mass = 108x + 7x = 115x
Given,
- Total mass of the coin = 230 mg
That means,
⇛ Total mass of the coin = 230 mg
⇛ 115x = 230 mg
⇛ x = 230 mg/115
⇛ x = 2 mg
Then,
- Mass of the steel = 108(2) = 216 mg
- Mass of the copper = 7(2) = 14 mg
☁️ ANSWER - 14 mg (Mass of copper)
<u>━━━━━━━━━━━━━━━━━━━━</u>
Answer:
2700!
Step-by-step explanation:
hope that helped <3
Answer:
B. 
Step-by-step explanation:
<em><u>To find the perimeter, use the formula:</u></em>
P = a + b + c
P = 12 + 12 + 9.7
P = 33.7
<em><u>To find area, use the formula:</u></em>
A = 
A = 
A = 
A = 54
