Question

Whats the formula to find the length of each side of a rhombus?

Answer 1

1 - All sides are congruent (equal lengths).

length AB = length BC = length CD = length DA = a.

2 - Opposite sides are parallel.

AD is parallel to BC and AB is parallel to DC.

3 - The two diagonals are perpendicular.

AC is perpendicular to BD.

4 - Opposite internal angles are congruent (equal sizes).

internal angle A = internal angle C
and
internal angle B = internal angle D.

5 - Any two consecutive internal angles are supplementary : they add up to 180 degrees.

angle A + angle B = 180 degrees
angle B + angle C = 180 degrees
angle C + angle D = 180 degrees
angle D + angle A = 180 degrees