O O The Circle Theorems O O O































































































- Slides: 95
O O The Circle Theorems O O O © T Madas
1 st Theorem © T Madas
The perpendicular bisector of a chord passes through the centre of the circle O © T Madas
The perpendicular bisector of a chord passes through the centre of the circle O © T Madas
The perpendicular bisector of a chord passes through the centre of the circle O © T Madas
Finding the Centre of Rotation © T Madas
The shapes below have been produced by rotation. Find the centre of rotation © T Madas
The shapes below have been produced by rotation. Find the centre of rotation © T Madas
The shapes below have been produced by rotation. Find the centre of rotation © T Madas
The shapes below have been produced by rotation. Find the centre of rotation © T Madas
nd 2 m e r o The © T Madas
Inscribed angles which correspond to the same arc are equal Inscribed Angle O © T Madas
Inscribed angles which correspond to the same arc are equal O Does this inscribed angle correspond to the same arc? © T Madas
rd 3 Theorem © T Madas
A central angle is twice as large as any inscribed angle which corresponds to the same arc Inscribed Angle O Cen tra l An gle © T Madas
O O Various Forms of the Theorem O O O © T Madas
th 4 Theorem © T Madas
O An inscribed angle which corresponds to a diameter (or semicircle) is a right angle © T Madas
5 th Theorem © T Madas
Opposite angles in a cyclic quadrilateral are supplementary O Cyclic Quadrilateral © T Madas
6 th Theorem © T Madas
A tangent and a radius drawn at any point on the circumference of the circle meet at right angles O Tangent poin t © T Madas
© T Madas 7 th Theorem
The intersection of two tangents to a circle is equidistant from their points of contact. [Their angle of intersection and the central angle formed by the radii at the points of contact, are supplementary] O © T Madas
th 8 Theorem © T Madas
sector t n e m seg O nt e m seg me nt g se © T Madas
O Alternating Segments © T Madas
The angle formed by a chord and a tangent at one of its endpoints is equal to the inscribed angle corresponding to the same chord in the alternating segment O © T Madas
Circle Theorem Test © T Madas
Circle Theorem Mini Test © T Madas
© T Madas
Practice Question 1 © T Madas
O 30° 150° 30° 45° 15° x 15° © T Madas
Practice Question 2 © T Madas
50° 30° O z 100° y 50° x 30° © T Madas
Practice Question 3 © T Madas
70° c 70° a 20° O 20° b © T Madas
Practice Question 4 © T Madas
n 40° 55° 85° 95° O m 40° p 55° © T Madas
Practice Question 5 © T Madas
x 25° O y 65° Tange nt poi nt © T Madas
Practice Question 6 © T Madas
s 55° O t 110° © T Madas
Practice Question 7 © T Madas
28° u 28° O v 56° © T Madas
Practice Question 8 © T Madas
h 150° 30° 60° O 300° © T Madas
Practice Question 9 © T Madas
130° 50° O c 100° © T Madas
Practice Question 10 © T Madas
a 25° O 50° b 25° © T Madas
a 25° O 130° 50° b 25° Can you solve this problem without a circle theorem? © T Madas
Practice Question 11 © T Madas
115° 65° O x 230° © T Madas
Practice Question 12 © T Madas
100° O z 200° © T Madas
Practice Question 13 © T Madas
b 138° 84° O a 42° © T Madas
Practice Question 14 © T Madas
O 296° f 64° 32° 148° 32° g 32° © T Madas
Practice Question 15 © T Madas
q 90° p 25° O 65° 115° © T Madas
Practice Question 16 © T Madas
O x 45° 90° © T Madas
Practice Question 17 © T Madas
B 70° AB = BC 90° 20° A r q 35° O p 55° C © T Madas
Practice Question 18 © T Madas
72° 90° O u 18° v 72° © T Madas
Practice Question 19 © T Madas
nt i o tp en g n Ta O a 60° b 120° c 60° 30° Tangent po int © T Madas
Practice Question 20 © T Madas
z 58° O x 32° y 58° © T Madas
Practice Question 21 © T Madas
85° 95° O 85° x 85° © T Madas
Practice Question 22 © T Madas
Can you think of another reason as to why both these angles are 57° ? 57° t 57° O r 123° © T Madas
Practice Question 23 © T Madas
y 62° x 124° O 56° 62° w 118° z 56° © T Madas
Practice Question 24 © T Madas
v 20° 155° 25° 135° O 4 u 5° 20° 160° © T Madas
Practice Question 25 © T Madas
x 240° O 120° 30° © T Madas
Practice Question 26 © T Madas
30° 75° O 75° x 60° © T Madas
Practice Question 27 © T Madas
72° O 144° 18° x 18° © T Madas
Practice Question 28 © T Madas
40° b 140° O a 50° 40° © T Madas
Practice Question 29 © T Madas
30° O 60° θ 30° © T Madas
Practice Question 30 © T Madas
25° O n 65° © T Madas
Practice Question 31 © T Madas
Exam question Tan gen tp oin t a 22° 68° c 124° 56° b 68° O d 68° oint p t n e Tang © T Madas
© T Madas