Question

a^2 + 4a + 4 = (a+2)^2, so it is a square

I don't understand why is this square, please help

Answer 1

Returning to your question of yesterday:
http://www.jiskha.com/display.cgi?id=1229063130

You know that the rectangle area is (a+2)^2 and that the width is (a+2). You were told that in the statement of the problem. Since the height of a rectangle is (area)/(width), the height (the other dimension) must also be a+2.

Answer 2

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