Proposed Problem 421.
Right Triangle, Cevian, Angles, Measurement.

Proposed Problem 422.
Triangle, 24, 30 degree, Angle, Congruence.

Proposed Problem 423.
Triangle, 30, 40 degree, Angle, Congruence.

Proposed Problem 424.
Triangle, Cevian, Angle, 90 degree, Congruence.

Proposed Problem 425.
Quadrilateral, Triangle, Angles, 10, 20, 50 degrees, Congruence.

Proposed Problem 426.
Triangle, Circumradius, Circumcenter, concurrent Cevians.

Proposed Problem 427.
Triangle, Two Altitudes, Square of a Side.

Proposed Problem 428.
Quadrant of a circle, Square, Angle bisector, Measurement.

Proposed Problem 429.
Circumscribed and Inscribed Regular Pentagon, Perpendicular, Measurement.

Proposed Problem 430.
Circumscribed and Inscribed Regular Pentagon, Perpendicular, Areas.