## How can you prove that an isosceles triangle is congruent?

Hence proved. Theorem 2: Sides opposite to the equal angles of a triangle are equal. Proof: In a triangle ABC, base angles are equal and we need to prove that AC = BC or ∆ABC is an isosceles triangle….Isosceles Triangle Theorems and Proofs.

MATHS Related Links | |
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Reflection Symmetry | Surface Area Of A Cone |

**How do you find the altitude of an isosceles triangle?**

Altitude of an isosceles triangle = h=√a2−b24 h = a 2 − b 2 4 ; where ‘a’ is one of the equal sides, ‘b’ is the third side of the triangle.

**What are the rules of an isosceles triangle?**

An Isosceles Triangle has the following properties:

- Two sides are congruent to each other.
- The third side of an isosceles triangle which is unequal to the other two sides is called the base of the isosceles triangle.
- The two angles opposite to the equal sides are congruent to each other.

### How many altitudes does an isosceles triangle have?

The altitude to the base of an isosceles triangle bisects the base. When the altitude to the base of an isosceles triangle is drawn, two congruent triangles are formed, proven by Hypotenuse – Leg….

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4. | 4. Reflexive Property (A quantity is congruent to itself.) |

**How do you prove equilateral?**

Answer: If three sides of a triangle are equal and the measure of all three angles is equal to 60 degrees then the triangle is an equilateral triangle. The distance formula can be used to prove that a triangle is an equilateral triangle.

**How to prove that a triangle is an isosceles triangle?**

Theorem 2: Sides opposite to the equal angles of a triangle are equal. Proof: In a triangle ABC, base angles are equal and we need to prove that AC = BC or ∆ABC is an isosceles triangle. Construct a bisector CD which meets the side AB at right angles. Or ∆ABC is isosceles.

## What are the angles opposite to the equal sides of isosceles?

Theorem 1: Angles opposite to the equal sides of an isosceles triangle are also equal. Proof: Consider an isosceles triangle ABC where AC = BC. We need to prove that the angles opposite to the sides AC and BC are equal, that is, ∠CAB = ∠CBA. We first draw a bisector of ∠ACB and name it as CD.

**Are the altitudes of an isosceles triangle of equal length?**

If a triangle is isosceles, then the two altitudes drawn from vertices at the base to the sides are of equal length. Let ABC be an isosceles triangle with sides AC and BC of equal length ( Figure 2 ). We need to prove that the altitudes AD and BE are of equal length.

**How many congruent sides does an I sosceles triangle have?**

An i sosceles triangle has two congruent sides and two congruent angles. The congruent angles are called the base angles and the other angle is known as the vertex angle.