Triangle angle sum and exterior anglesHSG.CO.C.10Use the triangle angle sum (180°) and the exterior angle theorem to find missing angles and solve for x.Triangle inequality theoremDecide whether three lengths can form a triangle, and find the possible lengths of a third side from the other two.Triangle congruence (SSS, SAS, ASA, AAS, HL)HSG.SRT.B.5Match given pairs of equal sides and angles to the SSS, SAS, ASA, AAS and HL congruence rules, and spot SSA and AAA, which prove nothing.Triangle midsegment theoremHSG.CO.C.10Use the midsegment theorem: a segment joining the midpoints of two sides is parallel to the third side and half as long.
Geometry Triangles & congruence Worksheets
The triangle angle sum and exterior angles, the triangle inequality, the midsegment theorem and the SSS, SAS, ASA, AAS and HL congruence rules. Every sheet comes with a computed answer key.
Make a mixed triangles & congruence sheet