Question

Triangle ABC, is an isosceles triangle, angle A=40°. Find angle ACD​

Answer 1

Answer:

Triangle ABC is an isosceles triangle

Angle A = 40°

AB = AC Isosceles triangle property

Angle A = Angle C [ Angle opposite to equal side are equal ]

In Traingle ABC

Angle A + B + C = 180° [ Angle sum property]

40° + 2(B) = 180°

2(B) = 180 - 40

2(B) = 140

B = 140/2

B = 70

Since angle B = Angle C

Therefore, Angle ACB is 70°

Answer 2

$\mathsf{\huge{\underline{Answer}}}$

Angle ACB = 70°

$\rule{200}{2}$

$\mathfrak{\large{\underline{\underline{Explanation}}}}$

ABC is an isosceles triangle

So,

angle A = 40°

And angle B = C

( Property of isosceles triangle)

Let angle B be x

So,

A + B + C = 180° (Angle Sum Property)

___________[ Put values]

40° + x +x = 180°

2x = 140°

x = 140°/2

x = 70°

____________[Answer]___________

$\rule{200}{2}$

So, angle ABC AND ACB BOTH ARE OF 70°