If line AD is a tangent to circle B at point C, and m∠ABC = 40º, what is the measure of ∠BAC? 90º 180º 50º 40º

Mathematics

2 answers:

sveticcg [70]3 years ago

5 0

Answer:

Step-by-step explanation:

zhenek [66]3 years ago

4 0

We have a line tangent to the circle with center B at point C. We know that the angle formed between the tangent line at the point of intersection to the line extended from that point to the center of the circle is equal to 90°. In the problem, the 90° is for ∠BCA. We also know that the summation of all angles in a triangle is 180°. We have the solution below for the ∠BAC
180°=∠BAC + ∠BCA + ∠ABC
180°=∠BAC + 90° + 40°
∠BAC =50°
The answer is 50°.

You might be interested in

An aptitude test has a mean score of 80 and a standard deviation of 5. The population of scores is normally distributed. What pr

konstantin123 [22]

Answer:

2.28% of tests has scores over 90.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 80, \sigma = 5$