ABC is a triagle in which DE||BC. Find ` angle A `.

ABC is a triangle in which DE||BC and AD:DB = 5:4. Then DE:BC is

Let ABC and DEF be two triangles in which AB = DE, BC = FD and CA = EF. The two triangles are congruent under the correspondence ABC leftrightarrow ______

ABC is a right angled triangle in which angleB=90^(@) and AB=BC . Find angleA and angleC .

ABC is a right triangle, right angled at C and AB = sqrt2 BC. Then, find angle ABC.

In a Delta ABC, angle B=100^(@), angle C=70^(@), AE _|_ BC & AD is angle bisector . Find angle EAD .

The given figure shows an isosceles triangle ABC with AB = BC and angle B = 20^(@) . Points D&E are on AB & BC respectively so that the measure of angle CAE is 40^(@) degrees and the measure of angle ACD is 50^(@) degrees. DE and AC meet at F. Find the measure of angle AFD.

/_ABC is right angled triangle in which /_A is 90^(@) Semi cight angled triangle in which /_A BC as diameters.Find the area of the shaded region

ABC is rt angled triangle angleBAC=90^(@) and angleACB=60^(@) . What is the ratio of the circum radius of the triagle to the side AB?