Answer:
Both the boats will closet together at 2:21:36 pm.
Step-by-step explanation:
Given that - At 2 pm boat 1 leaves dock and heads south and boat 2 heads east towards the dock. Assume the dock is at origin (0,0).
Speed of boat 1 is 20 km/h so the position of boat 1 at any time (0,-20t),
Formula : d=v*t
at 2 pm boat 2 was 15 km due west of the dock because it took the boat 1 hour to reach there at 15 km/h, so the position of boat 2 at that time was (-15,0)
the position of boat 2 is changing towards east, so the position of boat 2 at any time (-15+15t,0)
Formula : D=
⇒ 
Now let 
∵ 
⇒ t= 450/1250
⇒ t= .36 hours
⇒ = 21 min 36 sec
Since F"(t)=0,
∴ This time gives us a minimum.
Thus, The two boats will closet together at 2:21:36 pm.
Let c= cost to rent each other
Let t= cost to rent each other
2c+3t=25
6T+5T=49
Multiply the 2nd equation by (-2) and add equation together
2c+3t=25
-12c-10t= 98
2t=98
T=49
Put this value into the 1st equation solve c
2c+3(49)=49
2c+147=49
2c=98
C=49
Cost to each chair and table are same 49.
-3x - y = -17
4x + 2y = 20
multiply one part of the equation so that we can be able to use the process of elimination.
(-3x - y = -17)2
4x + 2y = 20
Now we have:
-6x -2y = - 34
4x+2y= 20
------------------------
-2x = -14
Divide -2 on both sides.
-2x = -14
/-2 /-2
x = -7.
=============================================
To solve for y, we just have to substitute the value of x to any of the equation given above, that we feel comfortable with. And I'm going to choose this equation: 4x + 2y = 20
4x + 2y = 20
4(-7) + 2y = 20
-28 + 2y = 20
Add 28 on both sides
-28 + 2y = 20
+28 +28
---------------------
2y = 48
/2 /2
y = 24.
The last thing you would do is to check if the answers is correct.
All you have to do is plug in the values of x and y into both equations and see if they equal to one another.
You may have to do this by yourself :P
Anyways, if you have any questions about this topic, feel free to PM me or any other users interested. Thank you for being part of Brainly! Have a nice day!
Answer:
Lateral = 48 cm squared and Surface area = 60 cm squared
Step-by-step explanation:
Lateral surface area = 4 x 4 + 5x4( Slope) + 4 x 3 (Cross section x2) = 48
Surface area: Lateral + 4x3(base)
Answer:
AC = 55°
Step-by-step explanation:
In this geometry, arcs AC and BD have the same measure. The sum of the parts of arc CD will total the measure of CD.
AC + AB + BD = CD
2AC +80 = 170
AC = 110/2 = 55
The measure of arc AC is 55°.