Circle Theorems: Angle in a semicircle is 90 degrees

Circle Theorems: Angle in a semicircle is 90 degrees

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Lesson details

Key learning points

  1. In this lesson, we will learn that the angle in a semicircle is 90 degrees when the angle is subtended from the diameter. We will prove this result with a general case.

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3 Questions

Q1.
Work out the size of angle x.
An image in a quiz
225º
300º
Correct answer: 75º
90º
Q2.
Work out the size of angle x.
An image in a quiz
144º
18º
324º
Correct answer: 72º
Q3.
Work out the size of angle x.
An image in a quiz
112º
124º
Correct answer: 28º
56º

3 Questions

Q1.
Work out the size of angle x.
An image in a quiz
180º
30º
45º
Correct answer: 90º
Q2.
Work out the size of angle y.
An image in a quiz
147º
22º
Correct answer: 57º
90º
Q3.
Work out the size of angle x.
An image in a quiz
122º
Correct answer: 32º
45º
58º

Lesson appears in

UnitMaths / Circle Theorems 1