11None interested in geometry??
This is an ISI question.
1.Consider a circle with centre O.2 chords AB and CD extended intersect at a point P outside the circle.If <AOC=43 and <BPD=18,then the value of <BOD is:
a.36
b.29
c.7
d.25
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3 Answers
1
Now <ADC =21.5° as it is the angle subtended at circumference so it'l b half that of that at centre..
so <DAB = 21.5° - 18°=3.5°
Now <dab is the angle subtended at circumference and <BOD is the angle at the centre..
So <BOD=2<DAB=7°
36the question is just sum nd difference...
join AC
LPAC + LPCA = 162°
LOAC + LOCA = 137°
SO LBAP + LDCO = 25°
=> 180 - 2LBAP + 180 - 2LDCO = 310°
THUS LBOD = 360 - (310 + 43)
= 360 - 353 = 7°