Line and angles, parallels, triangles, congruence, inequalities, parallelograms, applications of parallels, bisectors, perpendiculars etc.

If the diagonals of a parallelogram are perpendicular to each other, then it is a

In a triangle ABC, ∠A = 100° and sides AB and AC are equal. Then value of ∠B is

For the given figure, the values of x and y are respectively

What is the measure of each angle of a rectangle?

An object of height 90 cm is moved away from the base of lamp post at a speed of 1.2 m/s. If the lamp is 3.6 m above the ground, then the length of the shadow of object after 4 seconds will be

In a $\Delta$ ABC, if AB < BC < CA, then which of the following is true?

In the given figure, ABCD is a parallelogram. Then which of the following is true about x and y?

In the given figure, ABC is an isosceles triangle such that AB = BC. The lines DE and FG are parallel to AB. Then which of the following option is not true ?

In the given figure, the value of x will be :

In the given figure, ABCD is a cyclic quadrilateral in which AC and BD are its diagonals. If ∠DBC = 55° and ∠BAC = 45°, then the value of ∠BCD will be :

In the given figure, lines PQ and RS intersect each other at point O. If ∠POR : ∠ROQ = 5 : 7, then the value of ∠POS will be :

In a triangle PQR, if side PQ = PR, then: