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A square can be constructed using a few known measurements.
The measurements are:
1. When the side is known.
2. When the diagonal is known
Method 1: When the side is known
Let us construct a square with 5 cm as its side. Let us also find the area of the square obtained.Step 1: Draw a rough diagram for the measurements given.
Step 2: Draw a line segment AB of length 5 cm.
Step 3: With A as centre, draw a perpendicular line.
Step 4: With A as centre and with 5 cm as radius, draw an arc on the perpendicular line. Mark the intersection as D.
Step 5: With D as centre and with 5 cm as radius, draw an arc. Similarly, with B as centre and with 5 cm as radius, cut the existing arc. Mark the intersection as C.
Step 6: Join BC and CD to form the desired square.
To find the area of the square:
\text{Area of a square} = \text{Side} \times \text{Side}
\text{Area of a square} = \text{Side}^2
Here, \text{Side} = 5 cm.
Therefore, \text{Area of a square} = 5^2
= 25 cm^2
Method 2: When the diagonal is known
Let us construct a square with one of its diagonals as 10 cm. Let us also find the area of the square obtained.
Step 1: Draw a rough diagram with the measurements known.
Step 2: Draw a line segment AC of length 10 cm.
Step 3: Draw a perpendicular bisector to AC such that the bisector intersects AC at O.
Step 4: With O as centre and with 5 cm as radius, draw arcs on both sides of the perpendicular bisector. Mark the intersections as B and D.
Step 5: Join AB, BC, CD, and AD to form the desired square.
To find the area of the square:
\text{Area of a square} = \text{Side} \times \text{Side}
\text{Area of a square} = \text{Side}^2
Here, side is unknown.
Therefore, we should measure the length of the side manually.
On measuring, we found that, \text{Side} = 7.1 cm
Now, \text{Area of a square} = 7.1^2
= 50.41 cm^2