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Examination paper for senior high school entrance examination of mathematics in grade three.
Make do with claw chickens without mathematical symbols.

( 1)

Connect CF connect OF

Because HF is tangent to circle O.

So HF is perpendicular to OF.

Because BC is parallel to CH

So OH is perpendicular to BC

Because it passes through the center of the circle

So BF=CF

So the angle 1 equals the angle 2.

So AF bisects the angle BAC

(2)

In the circle o, the angle 2 is equal to the angle FBC.

Because BD bisecting angle ABC angle 1 equals angle 2.

Angle ABF equals angle DBC+ angle FBC, and angle BDF equals angle 1 plus angle ABD.

So DBF angle equals BDF angle.

So BF equals DF.

(3)

Because the angle CBF is equal to the angle 1 and the angle BFA is equal to the angle BFA.

So the triangle ABF is similar to the triangle BFE.

So EF ratio BF is equal to BF ratio AF.

Because BF equals DF equals EF+DF equals 7.

4|7=7|AF

AF is equal to 49 out of 4.

AD is equal to 2 1.