The radius of circle O is 28, and OC =9. What is the length of AB?

1 answer:

7 0

The answer:
the complement of the question proposed one of the choices given beneath:
a) 58.8
b) 53.0
c) 29.4
d) 26.5

as we observe at the figure, AOB an isosceles triangle, and OCB is a right triangle

consider OCB
OC =9, OB= radius = 28
the problem is how to find the length of CA, for that C is a midpoint of segment AB, so AC=BC

BC can be found by using pythagorean theorem
OB²= OC² + CB², this implies CB² = OB² - OC²

CB² = 28² - 9² = 784 - 81=703, therefore CB= sqrt (703)=26.51

CB=26.51, since CB= AC, so AC=CB= 26.51

finally the the length of AB is AB = 2 x CB = 2x AC= 2x 26.51= 53.0

the answer is b) 53.0

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What are the endpoint coordinates for the midsegment of △BCD that is parallel to BC?

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Answer:

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Step-by-step explanation:

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Now, the endpoints of the mid-segment of $\triangle BCD$ which is parallel to $BC$ will be the mid-points of sides $BD$ and $CD$ .

Formula for the coordinate of mid-point : $(\frac{x_{1}+x_{2}}{2}, \frac{y_{1}+y_{2}}{2})$ , where $(x_{1}, y_{1})$ and $(x_{2}, y_{2})$ are two endpoints.