Answer of question 6:
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We should know that the tangent lines to the circle from the same points are equal.
So, the length of each tangent line from A = 2
the length of each tangent line from B = 5
the length of each tangent line from C = 3
Δ ABC consisting of the tangent lines of the circle
The perimeter of Δ ABC = sum of all tangent lines = 2*2 + 2*5 + 2*3 = 20
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Answer of question 14:
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1. The measure of a° = 2 * an inscribed angle facing the arc a°
= 2 * 40° = 80
2. The angles 40° and b° are alternate angles because of the parallel lines and the transversal line
∴ b° = 40°
3. The inscribed angles which faces the same arc are equal
So, the angles 40° , c° faces the arc a°
∴ c° = 40°
4. ∵ The sum of all angles of the triangle = 180°∴ b° + c° + d° = 180
∴ d° = 180 - (b° + c°) = 180° - ( 40° + 40° ) = 180° - 80° = 100°
Conclusion of the answer:
1. a° = 80 , 2. b° = 40° , 3. c° = 40° , 4. d° = 100°