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4. 1st drop down answer A. 90B. 114C. 28.5D. 332nd drop down answer choices A. Parallel B. Perpendicular 3rd drop down answer choices A. 180 B. 360 C. 270D. 90 4th drop down answer choices A. 33B. 57C. 90D. 28

4. 1st drop down answer A. 90B. 114C. 28.5D. 332nd drop down answer choices A. Parallel-example-1
User Tfhans
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1 Answer

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20 votes

Answer:

Tangent to radius of a circle theorem

A tangent to a circle forms a right angle with the circle's radius, at the point of contact of the tangent.

Part A:

With the theorem above, we will have that the tangent is perpendicular to the line radius drawn from the point of tangency

Therefore,

The value of angle CBA will be


\Rightarrow\angle CBA=90^0

Part B:

Since the angle formed between the tangent and the radius from the point of tangency is 90°

Hence,

The final amswer is

Tangent lines are PERPENDICULAR to a radius drawn from the point of tangency

Part C:

Concept:

Three interior angles of a triangle will always have the sum of 180°

Hence,

The measure of angles in a triangle will add up to give


=180^0

Part D:

Since we have the sum of angles in a triangle as


=180^9

Then the formula below will be used to calculate the value of angle BCA


\begin{gathered} \angle ABC+\angle BCA+\angle BAC=180^0 \\ \angle ABC=90^0 \\ \angle BAC=57^0 \end{gathered}

By substituting the values,we will have


\begin{gathered} \operatorname{\angle}ABC+\operatorname{\angle}BCA+\operatorname{\angle}BAC=180^(0) \\ 90^0+57^0+\operatorname{\angle}BCA=180^0 \\ 147^0+\operatorname{\angle}BCA=180^0 \\ substract\text{ 147 from both sides} \\ 147^0-147^0+\operatorname{\angle}BCA=180^0-147^0 \\ \operatorname{\angle}BCA=33^0 \end{gathered}

Hence,

The measure of ∠BCA = 33°

User Thiago Melo
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