Table of Contents

- 1 Can you prove triangle congruence by AAA?
- 2 What is the AAA congruence theorem?
- 3 Which criteria can be used to prove triangles are congruent?
- 4 How do you prove that a trapezoid is congruent?
- 5 Is the opposite sides of a trapezium are parallel?
- 6 Is opposite side of trapezium are equal?
- 7 How do you tell if a trapezium is regular or irregular?
- 8 What are the properties of a trapezium?

## Can you prove triangle congruence by AAA?

Four shortcuts allow students to know two triangles must be congruent: SSS, SAS, ASA, and AAS. Knowing only angle-angle-angle (AAA) does not work because it can produce similar but not congruent triangles.

### What is the AAA congruence theorem?

may be reformulated as the AAA (angle-angle-angle) similarity theorem: two triangles have their corresponding angles equal if and only if their corresponding sides are proportional.

**How do you prove that the sides of a trapezium are parallel?**

- It is only with isosceles trapezium and not the other kind.
- Draw the isosceles trapezium and name them ABCD, AB (longer side) being parallel to CD (shorter side).
- Extend AD and BC to meet at P.
- The supplementary angles of

**Is AAA a postulate?**

In Euclidean geometry, the AA postulate states that two triangles are similar if they have two corresponding angles congruent. (This is sometimes referred to as the AAA Postulate—which is true in all respects, but two angles are entirely sufficient.) The postulate can be better understood by working in reverse order.

## Which criteria can be used to prove triangles are congruent?

ASA stands for “angle, side, angle” and means that we have two triangles where we know two angles and the included side are equal. If two angles and the included side of one triangle are equal to the corresponding angles and side of another triangle, the triangles are congruent.

### How do you prove that a trapezoid is congruent?

One way to prove that a quadrilateral is an isosceles trapezoid is to show:

- The quadrilateral has two parallel sides.
- The lower base angles are congruent and the upper base angles are congruent.

**How do you prove AAA?**

AAA Similarity

- Statement: If in two triangles, the corresponding angles are equal, i.e., if the two triangles are equiangular, then the triangles are similar.
- Given : Triangles ABC and DEF such that ∠A = ∠D; ∠B = ∠E; ∠C = ∠F.
- Prove that : Δ ABC ~ ΔDEF.

**Is AAA a similarity criterion?**

AAA Similarity Criteria : Two triangles are similar if all three angles of one triangle are equal to another triangle. If triangles are similar then corresponding sides are also proportional.

## Is the opposite sides of a trapezium are parallel?

The opposite sides of trapezium are parallel.

### Is opposite side of trapezium are equal?

We know, a trapezium has exactly one pair of parallel sides and the other two sides are non-parallel. Now a regular trapezium will have the other two non-parallel sides equal, whereas an irregular trapezium will have the other two non-parallel opposite sides, unequal.

**What is the difference between congurent and congruent trapezium?**

A congurent trapezium may be defined as the one having all its sides and angles equal to the corresponding sides and angles of another trapezium. A congruent trapezium may be defined as the one having all its sides and angles equal to the corresponding sides and angles of another trapezium.

**How many pairs of opposite sides of a trapezium are parallel?**

In trapezium, exactly one pair of opposite sides are parallel The diagonals intersect each other The non-parallel sides in the trapezium are unequal except in isosceles trapezium The line that joins the mid-points of the non-parallel sides is always parallel to the bases or parallel sides which is equal to half of the sum of parallel sides

## How do you tell if a trapezium is regular or irregular?

Now a regular trapezium will have the other two non-parallel sides equal, whereas an irregular trapezium will have the other two non-parallel opposite sides, unequal. For a regular or isosceles trapezium, the sets of angles adjoined by parallel lines are equal.

### What are the properties of a trapezium?

A trapezium has the following properties: Like other quadrilaterals, the sum of all the four angles of the trapezium is equal to 360°. A trapezium has two parallel sides and two non-parallel sides. The diagonals of regular trapezium bisect each other. The length of the mid-segment is equal to half the sum of the parallel bases, in a trapezium.