Cool circle
Geometry
Level
pending
Let, ABCD be a quadrilateral of area18 with side AB parallel to side CD&AB=2CD.
Let AD be perpendicular to AB&CD.If a circle is drawn inside the quadrilateral ABCD touching all the sides , then its radius is
The answer is 2.
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1 solution
image
Since
2
C
+
2
B
=
2
π
, use
t
a
n
2
B
t
a
n
2
C
=
1
and eliminate
x
using it and the area given.