Plane Geometry

AABC acute angle adjacent angles adjacent figure altitude Analysis angle equal angles are equal apothem base angles bisects central angle chord circle of radius circumscribed congruent triangles Construct a circle Construct an angle Corollary corresponding sides decagon diagonals diameter divided Draw drawn equal angles equilateral triangle EXERCISES exterior angle Find the area Find the length Find the locus Find the number Find the radius given angle given circle given line given point Hence hypotenuse inscribed angle intersect isosceles trapezoid isosceles triangle legs median meet mid-point number of degrees obtuse opposite sides parallelogram perimeter perpendicular bisector produced Proof Prove quadrilateral radii ratio rectangle regular inscribed regular polygon rhombus right angle right triangle secant similar triangles straight angle straight line supplementary angles Theorem trapezoid triangle ABC triangle are equal triangle whose sides triangles are congruent vertex angle vertices