What is the area of a rhombus with a 60 degree angle and sides 5 cm long?

A = hb = (5*sin60)*5 = 21.65cm^2.

To find the area of a rhombus, you can use the formula: Area = (diagonal1 * diagonal2) / 2. However, in this case, the given information is not sufficient to calculate the area using the formula.

To find the area of a rhombus with a 60-degree angle and sides of 5 cm long, we need to use a different approach. Since a rhombus with a 60-degree angle is an equilateral rhombus, we can imagine it as two equilateral triangles put together.

To calculate the area of an equilateral triangle, we can use the formula: Area = (side length^2 * √3) / 4.

Given that the side length of the rhombus is 5 cm, we can calculate the area of one equilateral triangle as follows:

Area of one equilateral triangle = (5 cm^2 * √3) / 4

Now, as our rhombus is composed of two equilateral triangles, we can calculate the total area of the rhombus by doubling the area of one triangle:

Total area of the rhombus = 2 * (5 cm^2 * √3) / 4

Simplifying the expression further:

Total area of the rhombus = 5 cm^2 * √3 / 2

Hence, the area of the rhombus with a 60-degree angle and sides of 5 cm long is 5 cm^2 multiplied by the square root of 3, divided by 2.