Question

in an isoceles triangle ABC, if AB=AC and A=90, find B​

Answer 1

Step-by-step explanation:

Answer:-

Given:-

• An Isosceles Triangle.
• The sides equal are AB and AC.

To find:-

Angle B

Concept:-

Angles acting in Isosceles Triangle.

Let's Do!

$90 + x + x = 180$

• x are the angles, which are same. Because the sides are same, the corresponding angles are also same. Hence, I considered them as x.

$2x = 180 - 90$

$2x = 90$

$x = \dfrac{90}{2}$

$x = 45 ^{ \circ}$

• So, Accordingly, we can say that angle B measures 45°, provided that one angle was 90°.
• And also we know that sum of all angles of a Triangle is 180°.
• And also, angle C also measures 45°, same corresponding angles.

Answer 2

$\huge\bf{\underline{\underline{Answer:}}}$

$\Huge{\boxed{\sf{\red{ \angle B = 45°}}}}$

__________________________

$\huge\bf{\underline{\underline{Explanation:}}}$

It is given that,

ABC is an isosceles triangle in which AB=AC and A=90°.

• We know that in an isosceles triangle, two sides and two angles are equal.AB=AC, then ∠B = ∠C

Let ∠B and ∠C be x.

$\implies{\sf{ \angle A + \angle B + \angle C = 180°}}$

• Reason : Angle sum property of a triangle.

Substituting the values, we get

: $\implies{\sf{ 90° + x + x = 180°}}$

: $\implies{\sf{ 90° + 2x = 180°}}$

: $\implies{\sf{ 2x = 180° - 90°}}$

: $\implies{\sf{ x = \dfrac{90°}{2}}}$

: $\implies{\sf{ x = 45°}}$

Therefore, ∠B = ∠C = x = 45°

Hence, the value of ∠B is 45°.

__________________________