Congruent angle

Similar polygons have the same shape (congruent angles) but can have different size. If you are told that two polygons are similar, then their corresponding sides are in proportion. 

Figure 12.2 Schematic representation of conjugate complement vectors X, X in the (Z, Z ) reference frame, showing congruent angles leading to the geometrical identities of (12.38). Projections of X, X onto the Z ordinate give additional congruencies used in other identities.

When two straight lines intersect at a vertex there are two pairs of congruent angles. Angles at the vertex that are opposite each other are called vertically opposite angles, and are equal in size. In this geometry theorem, vertically has no reference to the word vertical, but is derived from the word vertex (see figure a) ... 

Given a triangle, congruent sides are opposite congruent angles. In other words, equal sides are opposite equal angles. 

A triangle has two congruent sides, and the measure of one angle is 40 degrees. Which of the following types of triangles is it ... 

In the figure below, which of the following pairs of angles must be congruent ... 

Which of the angles in the figure must be congruent if lines / and m are parallel ... 

Are these two shapes equal Some people might say yes, because all their lengths and angles are the same others might say no they are in different positions and hence different. It all depends on what exactly you mean by equal, sometimes there are different degrees and kinds of equality (such as congruent and similar ). 

SIMILAR POLYGONS polygons with corresponding angles that are congruent, and corresponding sides that are in proportion... 

Because no sides are marked as congruent in this figure, the classification by sides is scalene. There is one angle greater than 90° (angle b is 105°) therefore, the angle classification is obtuse. This triangle is obtuse scalene. 

In the diagram above, angle OBC is congruent to angle OCB. How many degrees does angle A measure ... 

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