Below is a list of proofs you'll see during this course. If there's a theorem I've missed, please contact me.

- Linear pair theorem
- Area of a regular polygon
- Diagonal length of a right rectangular prism
- 3D distance formula
- 3D midpoint formula
- Two segments are congruent if and only if they have the same length
- Two angles are congruent if and only if they have the same measure
- Congruent supplements theorem
- Congruent complements theorem
- ASA congruence
- AAS congruence
- Isosceles triangle theorem
- Converse of the isosceles triangle theorem
- SSS congruence
- SAS congruence
- Converse of the Pythagorean theorem
- All circles are similar
- Third angle theorem
- Pythagorean theorem proof using similar triangles
- Parallel lines have the same slope
- Perpendicular lines have negative reciprocal slope
- Crossed ladders theorem
- Extended crossed ladders theorem
- Sum of interior angles for triangles (first proof)
- Sum of interior angles for triangles (second proof)
- Sum of interior angles for simple polygons
- Sum of exterior angles
- Perpendicular bisector theorem
- Converse of the perpendicular bisector theorem
- Circumcenter theorem
- Angle bisector theorem
- Incenter theorem
- The area of a triangle is equal to half its perimeter times the radius of its incircle
- Euler line theorem
- Geometric mean altitude theorem
- Geometric mean leg theorem
- AM-GM inequality (visual proof 1)
- AM-GM inequality (visual proof 2)
- AM-GM inequality (visual proof 3)
- AM-GM inequality (algebraic proof)
- Triangle angle bisector theorem
- Ceva's theorem
- The medians of a triangle are concurrent
- The angle bisectors of a triangle are concurrent
- The altitudes of a triangle are concurrent
- The altitude of an isosceles triangle cuts two congruent right triangles
- The three medians cut a triangle into six triangles of equal area
- In any triangle, the greater side subtends the greater angle
- In any triangle, the greater angle subtends the greater side
- Triangle midsegment theorem
- Trapezoid midsegment theorem
- Proportionality theorem
- Converse of the proportionality theorem
- Menelaus's theorem
- Side splitter theorem
- Hinge theorem
- Converse of the hinge theorem
- Hypotenuse-leg congruence theorem
- Hypotenuse-angle congruence theorem
- Area of a triangle on a grid
- Exterior angle theorem
- Diagonals of a kite are perpendicular
- Diagonals of a parallelogram bisect each other
- Diagonals of a rhombus are perpendicular bisectors
- Area of a rhombus from diagonals
- Diagonals of a rectangle are congruent
- Opposite sides of a parallelogram are congruent
- Opposite sides of a parallelogram are congruent
- Opposite angles of a parallelogram are congruent
- British flag theorem
- If a quadrilateral is cyclic, then its opposite angles are supplementary and each exterior angle is equal to the opposite interior angle
- Ptolemy's theorem (proof 1)
- Ptolemy's theorem (proof 2)
- Thales's theorem
- Converse of Thales's theorem
- Central angle theorem
- Angles standing on the same arc are congruent
- A radius is perpendicular to a segment if and only if the radius bisects the segment
- Two chords are congruent if and only if they're equidistant from the center
- Congruent tangents theorem
- Radius and tangent theorem
- Centers of two circles and their point of contact are collinear
- Radius of circle inscribed in a right triangle
- Radius of semicircle inscribed in a right triangle
- Alternate segments theorem (proof 1)
- Alternate segments theorem (proof 2)
- Power of a point