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The length of the shorter diagonal of a rhombus is 12 cm, and the size of one angle is 60°. Calculate the area and perimeter of the rhombus.

User Cory Foy
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Final answer:

The area of the rhombus is 72 cm² and the perimeter is 48 cm.

Step-by-step explanation:

A rhombus is a quadrilateral with all sides of equal length. In a rhombus, opposite angles are equal. We can use the given information to calculate the area and perimeter of the rhombus.

Calculation of Area:

The area of a rhombus can be calculated using the formula: Area = (diagonal1 * diagonal2) / 2.

Given that the length of the shorter diagonal is 12 cm and the longer diagonal is equal to the shorter diagonal:

Area = (12 * 12) / 2 = 144 / 2 = 72 cm²

Calculation of Perimeter:

The perimeter of a rhombus can be calculated by multiplying the length of one side by 4.

In a rhombus, all sides are equal. Let's say the length of one side is 's' cm:

Perimeter = 4s

We can find 's' using the law of cosines: cos(angle) = (s² + s² - 12²) / (2s * 2s)

cos(60°) = (s² + s² - 12²) / (4s²)

0.5 = (2s² - 144) / (4s²)

2s² - 144 = 0.5 * 4s²

2s² - 144 = 2s²

s² = 144

s = √144 = 12 cm

Perimeter = 4 * 12 = 48 cm

User Ksg
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