Prove two triangles are congruent by showing they satisfy one of four criteria. Find missing lengths by using the scale factor. The relationship between similar shapes may be expressed as a ratio.

A triangle is a polygon. It is a closed 3-sided shape made up of straight lines. The ‘tri-’ part of the word triangle means three. A triangle has 3 sides and 3 angles. Interior angles are the angles ...

1. Complete the following statements: (a) Two line segments are congruent if _____. (b) Among two congruent angles, one has a measure of 70°; the measure of the other angle is _____. (c) When we write ...