Write the sum of the angles of an obtuse triangle.

Prove that the sum of the three angles of a triangle is 180^0dot

If one angle of a triangle is equal to the sum of the other two angles, then the triangle is (a) an isosceles triangle (b) an obtuse triangle (c) an equilateral triangle (d) a right triangle

If one angle of a triangle is equal to the sum of the other two angles, then the triangle is

Fill in the blanks to make the following statements true: Sum of the angles of a triangle is ............ An exterior angle of a triangle is equal to the two ............ opposite angles. An exterior angle of a triangle is always ............ than either of the interior opposite angles. A triangle cannot have more than ............ right angles. A triangles cannot have more than ............ obtuse angles.

In an isosceles triangle, if the vertex angle is twice the sum of the base angles, calculate the angles of the triangle.

In an isosceles triangle, if the vertex angle is twice the sum of the base angles, then the measure of vertex angle of the triangle is (a) 100^0 (b) 120^0 (c) 110^0 (d) 130^0

By giving a counter example, show that the following statement is not true: p : if all the angles of a triangle are equal, then the triangle is an obtuse angled triangle.

Fill in the following blanks : In every triangle, the sum of (interior) angles of triangle = . . . . right angles.

If the sines of the angles A and B of a triangle ABC satisfy the equation c^2x^2-c(a+b)x+a b=0 , then the triangle (a) is acute angled (b) is right angled (c) is obtuse angled (d) satisfies the equation sinA+cosA ((a+b))/c

We know that the sum of the interior angles of a triangle is 180^0 . Show that the sums of the interior angles of polygons with 3,4,5,6 sides form an arithmetic progression. Find the sum of the interior angles of a 21 sided polygon.