A windmill has its center at (0, 0). Its blades make a complete rotation every 40 seconds. If the tip of one blade is positioned at (5, 6), after 30 seconds where is the tip of the blade located?

Question

danjs · Answer

do you know how to determine the equation of a circle given the center point and a point on the circle?

danjs · Answer

the general form for a circle is 

(x-h)^2 + (y-k)^2 = r^2

(h,k) is the center point, and r is the radius

danjs · Answer

centered at the origin , and the radius is the distance from (0,0) to (5,6) 

right?

danjs · Answer

actually, here is a simple way to see the solution ....

danjs · Answer

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danjs · Answer

since the angle of rotation is a nice one, it makes it pretty simple

danjs · Answer

you understand the picture?

anonymous · Answer

so would the answer be( -6,5)

danjs · Answer

almost, since it travels 30/40 of the way around, or 270 degrees, you end here...

anonymous · Answer

(6-5)

danjs · Answer

sorry, you start moving at angle A, not at angle zero, let me redo that

anonymous · Answer

okay

danjs · Answer

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