Question

In Fig. 12.14, there are five triangles. The measures of some of their angles have been indicated. State for each triangle whether it is acute, right or obtuse.

Answer 1

(i) This is a right angled triangle, as it contains a 90^o angle.
(ii) This is an obtuse angled triangle, as one of the angle(120^o) measures more than 90^o and less than 180^o._^​
(iii) This is an acute angled triangle, as all the angles are less than 90^o.
(iv) This is a right angled triangle, as it contains a 90^o angle.
(v) This is an obtuse angled triangle, as one of the angle (110^o) measures more than 90^oand less than 180^o._^​