Question

21. In the given figure, LABC - 75", ZACB 10" , find ZBDC​

Answer 1

Answer:bss aako values change krni h calculate rlena ans aajayga

thx

Given: ∠BAD=65

o

,∠ABD=70

o

,∠BDC=45

o

(i) ∵ ABCD is a cyclic quadrilateral.

In Δ ABD,

∠ BDA +∠ DAB +∠ ABD=180

o

By using sum property of Δ

s

∴ ∠BDA =180

o

−(65

o

+70

o

)

=180

o

−135

o

=45

o

Now from Δ ACD,

∠ADC =∠ADB+∠BDC

=45

o

+45

o

(∵∠ BDA=∠ADB=45

o

)

Hence, ∠D makes right angle belongs in semi-cricle therefore AC is a diameter of the circle.

(ii) ∠ACB=∠ADB (Angles in the same segment of a circle)

∴ ∠ACB=45

o

(∵∠ ADB=45

o

).