Question

In an isosceles triangle with two congruent sides, the angles across from the legs are called ________ angles.

Answer 1

The angles across from the legs are called as $\boxed{\text{\bf base angles}}$.

Further explanation:

Consider $\triangle\text{ABC}$ as an isosceles triangle whose sides are AB, BC, CA as shown in attached Figure 1.

In an isosceles triangle the two sides are equal and the angles corresponding to the opposite sides are equal.

In Figure 1 it can be seen that the side AB and BC are equal and $\angle\text{ABC}$ and $\angle\text{ACB}$ are also equal.

These two equal sides AB and BC are known as legs and the third side BC is base.

The angles $\angle\text{ACB}$ and $\angle\text{ABC}$ are called as the base angle and the third angle $\angle\text{BAC}$ is the vertex angle.

As per the angle sum property in $\triangle\text{ABC}$, the sum of three angles is equal to $180^{\circ}$.

The angles of $\triangle\text{ACB}$ is calculated as,

$\angle\text{ACB}+\angle\text{ABC}+\angle\text{CAB}=180^{\circ}$

Thus, the angles across from the legs are called as $\boxed{\text{\bf base angles}}$.

Learn more:

1. A problem on triangles brainly.com/question/2992432

2. A problem on line brainly.com/question/1473992

3. A problem on permutation brainly.com/question/5199020

Answer details:

Grade: Middle school

Subject: Mathematics

Chapter: Geometry

Keywords: Triangle, coordinate geometry, angles, sum, side, leg, equal, isosceles, base angle, vertex angle, corresponding sides, opposite sides.

Answer 2

Answer:

The angles across from the legs are called base angles

Step-by-step explanation:

we know that

The isosceles triangle is a triangle with two equal angles and two equal sides

The two equal sides are called legs and the third side is called base

The two equal angles are called base angles and the third angle is called vertex angle