Question

An isosceles triangle has two congruent sides, and the

Answer 1

Answer with Step-by-step explanation:

Isosceles triangle :In this triangle two sides are congruent and the angles opposite those sides are congruent.

Right triangle: In this triangle ,one angle is equal to 90 degree.

Suppose a right triangle ABC in which

Angle A=Angle B,Angle C=90 degree

$\angle A+\angle B+\angle C=180^{\circ}$

Using triangle angles sum property

Substitute the values

$\angle A+\angle A+90=180$

$2\angle A=180-90=90$

$\angle A=\frac{90}{2}=45^{\circ}$

Therefore,

A right triangle in which two equals angle are of 45 degree then the right triangle is an isosceles triangle.

Hence, River's statement is incorrect.