Answer:
A.78
Step-by-step explanation:
DONT TRUST ME
Answer: Choice C. 107.9 degrees (approximate)
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Explanation:
Draw a line segment from A to B. Mark point E as the intersection between this new line segment and the arc CD.
We can see that AE = 4000 because it's another radius of the same circle. The diagram shows that EB = 2800.
So,
AB = AE+EB = 4000+2800 = 6800
Because point D is a tangent point, this means radius AD is perpendicular to tangent segment BD. We have a 90 degree angle at point D, or we can write angle BDA = 90.
With triangle BDA being a right triangle, we can use a trig ratio to compute angle DAB. I'll call this angle A for short.
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Apply the cosine ratio. Focus entirely on triangle BDA.
cos(angle) = adjacent/hypotenuse
cos(A) = AD/AB
cos(A) = 4000/6800
cos(A) = 10/17
A = arccos(10/17)
A = 53.9681209275294 ... make sure your calc is in degree mode
A = 53.968
Angle DAB = 53.968 degrees approximately
This represents exactly half of central angle CAD, so we'll double the value to get 2*53.968 = 107.936 which rounds to 107.9 degrees showing why choice C is the answer.
Central angle CAD is exactly equal to the arc it cuts off, minor arc CD. The central angle is roughly 107.9 degrees of a full 360 degree circle, and the same can be said about the outer arc edge piece of minor arc CD.
Answer: You could say that it gives a reasonable accurate measure for most students.
If you use the function, you will get the following values for each student.
Mike 86, Terrel 50, Janie 66, and Melissa 106
For the first two students, the equation produces a score that is almost perfect. For the second two students, the scores are off by 14 and 16.
Overall, it is not a bad trendline for the data.