SOLUTION: A Square has a diagonal of 7cm. What is the area?

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Question 397249: A Square has a diagonal of 7cm. What is the area?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

A Square has all sides same; let the side be a
a diagonal d+=+7cm
a diagonal divides a square into two right triangles, so we will use Pythagorean Theorem to find a
d%5E2+=+2a%5E2
%287cm%29%5E2+=+2a%5E2
49cm%5E2+=+2a%5E2
49cm%5E2%2F2+=+a%5E2
24.5cm%5E2+=+a%5E2
a+=+sqrt%2824.5cm%5E2%29+.........we can round it to sqrt%2825cm%5E2%29
a+=+sqrt%2825cm%5E2%29+
a+=+5cm+
the area will be:
A+=+a%5E2
A+=+%285cm%29%5E2
A+=+25cm%5E2