I is the incentre of an isosceles triangle ABC. If angle B =80°, then the value of angle AIC is

Question

I is the incentre of an isosceles triangle ABC. If angle B =80°, then the value of angle AIC is (A) 120° (B) 135° (C) 130° (D) 115°

Tardigrade Admin · Accepted Answer

<img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/mathematics/18e7dadc79c8185914e79426b315c8c6-.png" /> angle AIC =90°+( angle B/2)=90°+40°=130°

Q. I is the incentre of an isosceles triangle $A BC$ . If $∠ B = 8 0^{\circ}$ , then the value of $∠ A I C$ is

$12 0^{\circ}$

$13 5^{\circ}$

$13 0^{\circ}$

$11 5^{\circ}$

$∠ A I C = 9 0^{\circ} + \frac{∠ B}{2} = 9 0^{\circ} + 4 0^{\circ} = 13 0^{\circ}$

Q. I is the incentre of an isosceles triangle ABC. If ∠B=80∘, then the value of ∠AIC is

120∘

135∘

130∘

115∘