Because it's also a 4 sided quadrilateral.
A square.
The square of 9 more than a number is equal to nine more than the square of a number. What is the number?
It has 3 more triangular faces than square faces
-4
One more.
-4
At minimum, 427. Depending on the exact geometry, you might need more than that.
Rectangle or a square
No, a square inch is more than 4 times bigger.
fire
Quadrilateral is a broad category. Within the category quadrilateral, you have trapezoid, rhombus, square, rectangle, and more.
An octagon is a polygon. The name refers to its shape, not its size. It can have an area of less than a billionth of a square foot to more than a billion square feet.