Calculate the perimeter of rhombus whose diagonals are 12 cm and 5 cm long.A.13 cmB.26 cmC.39 cmD.52 cm

To calculate the perimeter of a rhombus when the lengths of its diagonals are given, you can use the following formula:

Perimeter = 4 * side length

In a rhombus, the diagonals bisect each other at right angles, forming four congruent right triangles. The hypotenuse of each right triangle is half of the diagonal length.

Let's denote the length of one-half of the longer diagonal as "a" (which is 12 cm/2 = 6 cm), and the length of one-half of the shorter diagonal as "b" (which is 5 cm/2 = 2.5 cm). Now, you can find the side length "s" using the Pythagorean theorem:

s^2 = a^2 + b^2
s^2 = (6 cm)^2 + (2.5 cm)^2
s^2 = 36 cm^2 + 6.25 cm^2
s^2 = 42.25 cm^2

Now, take the square root of both sides to find "s":

s = √(42.25 cm^2)
s = 6.5 cm (approximately, rounded to one decimal place)

Now that you have the side length, you can calculate the perimeter:

Perimeter = 4 * s
Perimeter = 4 * 6.5 cm
Perimeter = 26 cm

So, the perimeter of the rhombus is 26 cm, which corresponds to option B.