Question

In triangle ABC, if angle AB = 4 cm, angle A = 50° and angleB = 80°, then the length of BC is :

a.7cm
b.6cm
c.4cm
d.3cm
​

Answer 1

Answer:

C- 4cm

Step-by-step explanation:

Let,

angle C=x°

In a triangle

angle A+angle B +angle C =180°

50°+80°+x°= 180°

130°+x° =180°

x°=180-130

x°=50°

hence,

triangle ABC is an isosceles triangle

AB=BC

AB=BC=4cm

therefore BC=4cm