Answer:
B. Square
D. Rhombus
Step-by-step explanation:
If you take a rhombus ABCD, its all sides are congruent. Lets take E as the point where the diagonals of a rhombus meet. Now it is known fact that the point where diagonals meet, they bisect each other.
Since, for sides, AB , CD,AD and CB are congruent
For diagonals, AC = BD
As E is the bisecting point for diagonals,
AE = EC and ED = EB
Now by SSS postulate, we can prove that all four triangles formed by rhombus are congruent
ΔAED , ΔBEC , ΔEDC and ΔAEB are congruent
Now the angles
∠AED, ∠AEB, ∠CED and ∠CEB are congruent as well,
So, we know that sum of interior angles of any quadrilateral is 360°
So each angle is 360/4 = 90°
This calculation is valid for square as well.
