Finding the area of a square is very easy if you know the lengths of its sides, perimeter, or diagonals. Here's how to find it.
Step
Method 1 of 3: Using Side Length
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Step 1. Write down the side lengths
Suppose a square has a side length of 3 cm. Write it down.
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Step 2. Know the formula for finding the area of a square (Area=side^2)
Since all squares have the same side length, you just need to multiply the side length of the square by itself. If the side of a square is 3 cm, then you only need to square 3 cm to find the area of the square. 3cm x 3cm = 9cm2.
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Step 3. Don't forget to write the units in square form
You've finished it.
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Squaring the sides of a square is the same as multiplying the height of the square by the base.
Find the Area of a Square Step 3Bullet1
Method 2 of 3: Using a Known Diagonal Length
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Step 1. Measure the length of the diagonal of the square
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Step 2. Multiply the result of measuring the diagonal length of the square by itself
Square the length of the diagonal. Suppose a square has a diagonal of 5 cm. Now, square the length of the diagonal. 5cm x 5cm = 25cm2.
Method 3 of 3: Using a Known Perimeter
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Step 1. Multiply the perimeter by 1/4 to find the length of the side
This is the same as dividing the perimeter by 4. Since a square has four sides and each side is the same length, you can find the side length of a square simply by dividing the perimeter by 4. Let's say the perimeter of a square is 20 cm. Multiply 20 cm by 1/4: 20 cm x 1/4 = 5 cm. Thus, you know that the length of the side of the square is 5 cm.
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Step 2. Multiply the length of the side of the square by itself
Square the side length. Since you already know that the side length is 5 cm, you can square it to find the area of the square. Area = (5 cm)2 = 25 cm.2