Wednesday, 29 March 2023

Angle Properties Of A Circle


1) Find the value of x of following
a)
                                                               110
b)                                                           80                                                                 
c) 
                                                               100
c) 
                                                                  60
d) 
                                                                  60
e) 
                                                                  30
f) 
                                                             120
g) 
                                                               100
h) 
                                                              100
i) 
                                                              70
j) 
                                                              100
k) 
                                                                  50
l) 
                                                                  48
m) 
                                                                40

2) If O is the centre of the circle, 
Find the angle ABC if ang AOC=130.  115

3) If O is the centre of the circle, 
Find angle BAC if angle AOB and AOC is 80 and 110 respectively.                      85

4) If O is the centre of the circle, 
Find angle ACB if BCD=48.             42

5) If O is the centre of the circle, 
If DBC=65 find BAC.                             25

6) In the following figure below,
 Calculate the major angle ABC.    115

7) In the figure ∆ABC is an equilateral triangle,
 find the angle BDC.                       120

8) In the figure measure of arc ABC is 100°
Determine angle ADC, ABC.       50,130

9) figure A,B, C are 3 points on a circle such that the angles subtended by the chord AB and AC at the centre O are 80°, and 120° respectively.
Determine the angle BAC.                80

10) In the figure angle BDC=30, ABC=110°, 
Then find angle BCA.                       80°

11) In the given figure O is the centre of the circle. If angle BAC =50°, 
Then find angle OBC.                         40

12) In the figure below, angle BAP and CPD are 40° and 110, 
Find angle PDC.                                30

13) In the figure below, angle ABC and BDC are 110 and 30 
Then find angle ACB.                 40

14) In the figure below, angle BAC and DBC are 40° and 65° 
Then find angle BCD.                        75

15)
Calculate the measure of angle AOC.   140

16) In figure, A, B and C are three points on a circle such that angles subtended by the chords AB and AC at center O are 90° and 110°. respectively.
determine angle BAC.                         80

17) In figure, A, B, C are 3 points on a circle such that the angles subtended by chords AB and AC at the centre O are 80° and 120° respectively. 
Determine angle BAC and the degree measure of Arc BPC.             80°

18) figure O is the centre of the circle and the measure of arc ABC is 100°.
Determine angle ADC, angle ABC. 50,130

19) itn the figure O is the centre of the circle. The angle subtended by the arc BCD at centre 140°. BC is produced to P. 
Determine the angle BAD, DCB.    70,110

20) 
Find angle PQB were O is the centre of the circle.                             48

21) 
Chord ED is parallel to the diameter AC of the circle. Given angle CBE =65°, find the angle DEC.              25°

22) in the figure O and O' are centres of two circles intersecting at B and C. ACD is a straight line.
 find x.                                               130

23) In the figure O is the centre and PQ is a diameter. If angle ROS=40°
Find angle RTS .                                  70

24) In the figure angle ACB=40, angle DPB=120, 
Find angle CBD.                                 20

25) In the figure AB is the diameter of the circle such that Angle PAB= 40°.
Find angle PCA.                              50

26) In the figure O is the centre of the circle. Angle OAB and OCB are 20 and 55.
Find angle BOC and AOC.          70,70

EXERCISE-B

1) In the given below,
Find the measure of angle ABC.     115

2) In the following, figure ABCD is a cyclic quadrilateral whose sides AB is the diameter of the circle, through A, B, C, D. If angle ADC =140.
find angle BAC.                               50

3) ABCD is a cyclic quadrilateral in which AB || CD and Angle B= 65.
 Find the other angles in degrees.   65, 115, 115

4) The opposite angles of a cyclic quadrilateral are in the ratio 4:5. Find the angles in degrees.            80, 100

5) ABCD is a cyclic quadrilateral. If angle BCD and ABD are 100 and 70, then
Find angle ADB.                                   30

6) In the figure angle ADC=85
Then find the angle CBP.               85

7) In the figure PQRS is a cyclic quadrilateral.
Find the measures of each angles.  135,30,45,150

8) In the figure angle DBC and BAC are 70, 40,
Find angle BCD.                                     70

9) In the figure angle BDC and ACB are 35 and 40
Find angle ABC.                              105

10) In the given figure t∆ABC is an isosceles triangle with AB =AC and m(angle ABC)=50,
 find m(angle BDC) and m(angle BEC).   80, 100

11) ABCD cyclic quadrilateral in which AD|| BC. If angle A= 70, 
find the remaining angles.       110, 110,70

12) in the given figure below angle ABD=70, angle ADB=30,
Calculate BCD.                                       80

13) In the given figure below, angle ACB= 35, angle BDC= 50,
Find angle ABC.                                   95

14) in ∆ ABC , BE perpendicular to AC and CF perpendicular to AB which intercept each other at P. if angle A= 40°, find the angle BPC.                          140

EXERCISE- C

1) Are the following statements true or false:
 
a) A quadrilateral whose opposite angles are 85° and 115° is cyclic.
b) A parallelogram whose 1 angle is 100° is cyclic .
c) A rectangle is a cyclic quadrilateral.
d) A square is a cyclic quadrilateral.
e) A rhombus is a cyclic quadrilateral.
f) O is the circumcenter of the ∆ ABC and OD perpendicular to BC. Is angle BOD= angle A.
g) AB is the diameter of a circle and AC and BD are its two parallel chords. Is AD= BC

2) O is the circumcircle of the ∆ ABC . Find the value angleOBC+ angle BAC.  

3)  who is the circums centre of the triangle ABC find the value of angle OBC A + angle BAC

4) Find the area of a right angled triangle if the radius of a circumcircle is 2 cm.  6

5) Find area right angled triangle if the radius of the circumcircle is 5cn and altitude drawn to the hypotenuse is 4cm.  20

6) ∆ ABC is right angled at B . On AC, a point D is taisecond so that AD = DC and AB = BD. Find angle CAB.                   60

7) In the adjoining figure ; 
ABCD is a cyclic quadrilateral, angle CBQ =48° and a= 2b. Find the numerical value of b.        28

8) In the joining figure angle AOC=110;
Find angle ADC , angle ABC , angle OAC.   55, 125, 35

9) In the adjoining figure PQ= PR and angle PQR=70
find angle QAR.                     40

10) In the adjoining figure;
AC is a diameter of the circle. AB =BC angle angle AED =118. Calculate angle DEC, angle DAB.                    28,73


EXERCISE-D

1) In the given figure angle DBC=70 and BAC= 40
Find angle BCD.                                 70

2) In the figure ABCD is a cyclic quadrilateral; O is the centre of the circle. If angle BOD=160,
Find angle BPD.                                100

3) In the given figure ∆ ABC is an isosceles triangle with AB= AC and angle=50°.
Find angles BAD and BEC.       80, 100

4) In the figure ABCD is a cyclic quadrilateral whose side AB is a diameter of the circle through A, B, C,D. If angle ADC=130,
Find angle BAC.                                    40

5) In the figure C and D are points on the semi-circle described on BA as diameter. Given angles BAD, DBC are 70, 30.
Calculate angles ABD and BDC.    20,40

6) In the figure, O is the centre of the circle. The angle subtended by the arc BCD at the centre is 140°. BC is produced to P. 
Determine the angle BAD and DCP.    70 

7) In the figure BD = DC and angle DBC = 25.
Find the angle BAC.                            50

8) In the given figure angle A=60 and angle ABC =80°,
Find angles DPC and BQC.         40, 20

9) In the figure ∆ABC is an equilateral triangle. 
Find Angle BEC.                                  120

10) In the figure ∆ PQR is an isosceles triangle with the PQ= PR and angle PQR =35.
 Find the angles QSR and QTR.    110,70

11) In the figure, O is the centre of the circle. if Angle BOD=160,
Find the value of x and y.            80,100

12) ABCD is a cycle quadrilateral. If angle BCD =100 and angle ABD=70.
Find the angle ADB.                           30

13) In the given figure O is the centre of the circle.
Find angle CBD.                                 50

14) In the figure AB and CD are diameters of a circle with centre O. If angle OBD=50
Find the angle AOC.                           80

15) On a semi-circle with AB as diameter, a point C is taken, so that angle CAB=30. Find the the angles ACB and ABC .   90,600

16) In a cyclic quadrilateral ABCD if AB|| CD and Angle B =70°, find the remaining angles.                  70,110,110

17) In a cyclic quadrilateral ABCD, if angle A= 3 angle C. Find angle A.    135

18) In the figure, O is the centre of the circle and angle DAB=50. 
calculate the values of x and y.    100,130

19) In the figure angle BAC=60 and Angle BCA= 20
Find angle ADC.                                  80

20) In the figure,  if ABC is an equilateral triangle.
Find angle BDC and angle BEC.   60,120

21) In the figure O is the centre of the circle. If angle CEA=30,
Find the value of x and y , z.   150, 60,30

22) in the figure angle BAD =78 and angle DCF =x° and angle DEF=y°.
 Find the value of x and y.       78, 102

23) In a cyclic quadrilateral ABCD, if angle A - angle C=60°. Find the two smaller angles.                                   60

24) In the figure ABCD is a cyclic quadrilateral. 
Find the value of x.                      100 

25) if ABCD is a cyclic quadrilateral in which 
a) BC|| AD, angle ADC= 110 and BAC= 50°. Find angle DAC.                        60

b) angle DBC=80° and angle BAC=40. Find angle BCD.                                   60

c) angle BCD= 100 and angel ABD=70.  Find angle ADB.                                   30

26) ABCD is a cyclic trapezium with AD||BC. If angle B=70°, determine other three angles of the trapezium.    110,70, 110

MISCELLANEOUS

1) In the figure O is the centre of the circle. 
Find angle AEC and reflex AOC.    68,224

2) In the figure O is the centre and angle=70. 
Find angle OAB, OAC.                   55,35

3) ABCD cyclic quadrilateral EABF is a line such that angEAD=82°, ang FBC= 74, and angBDC=50°. find the obtuse angle between AC and BD.                      108

4) Determine the angle a, b and c
                                                  105,13,62

5) O is the centre of the circle.
Calculate angles APB and AOB.    79,158

6) In figure, O is the centre of the circle and AP= BP.
Find angle A and POA.                    45,90

7) In the figure, given AB= AC and angle ABC=68.
Find angle BPC.                                  44

8) In figure O is the centre of the circle.
Find the angle AQB and AMB.  52°30', 127°30'

9) In the figure, given that PS= SR, ang RPS=54, and ang PRQ= 26,
Find the angle TQR, RTQ.               72,8

10) In the figure, O is the centre of the circle.
Find angle PRQ and reflex POQ.     105, 210


11) In the figure, given AB|| DC.
Find the angle DCB, ABC.             65,115

12) In the figure ABCD is a cyclic quadrilateral. AE is drawn parallel to CB and DA is produced. If angle ADC =92, angle FAE= 20,  
determine angle BCD.                      108

13) In the figure angle A =55° and angle C= 62° and the altitude BE produced meets the circle at D. 
Determine angle ACD, DAC, ADB.   35, 28, 62

14) In the figure if y=x.
Determine angle PNS.                      30

15) In the figure angle BCE=30.
Find x if y=2x.                                       40

16) In the figure I is the in-centre of ∆ ABC . AI when produced meets the circumcircle of triangle of ∆ABC in D. If angle BAC= 66 and angle ACB =80.
Find angle DBC, IBC, BID.      33,17,50

17) In the figure, O is the centre of the circle.
Value of angle x + angle y is
a) x b) y c) z d) none

17) In the figure AB=AD= DC=PB and angle DBC =20.
 
Find the angle ABD, APB.      20,20

18) in the figure O is the centre and AE the diameter of the semicircle ABCDE. If AB= BC and angle AEC=50°, then 
find the angle CBE, CDE , AOB. 40,140,50

19) In the figure, if y= 32 and z= 40,
Determine x, if y + z =90 and also find the value of x.                                       45

20) In a triangle ABC, if angle A=60° and the bisectors of Angle B and angle C meets AC and AB at P and Q respectively and intersect each other at I, Find the value of BIC.                          120

21) ABCD is a cyclic quadrilateral. If AC bisects both the angles A and C, then find the angle ABC.                             90

22) In the figure, O is the centre of the circle and BC = OB. 
find the value of x.              
a) y b) 2y c) 3y d) 4y e) none 

23) In the figure, find angle BCD. 
where ABCD is a cyclic quadrilateral whose diagonals at P and angle DBC=60° and angle BAC=40°.            80

24) In the figure O is the centre of the circle arc ABC subtends an angle of 130° at centre O. AB is extended upto P. 
Find angle PBC.                                   65