To find the diagonal we need to know the length of one of the square's sides. We know the area and the area of a square is the length of one side squared:

a = s²

so the length of one side of the square is:

s = \( \sqrt{a} \) = \( \sqrt{4} \) = 2

The Pythagorean theorem defines the square of the hypotenuse (diagonal) of a triangle with a right angle as the sum of the squares of the other two sides:

c² = a² + b²
c² = 2² + 2²
c² = 8
c = \( \sqrt{8} \) = \( \sqrt{4 x 2} \) = \( \sqrt{4} \) \( \sqrt{2} \)
c = 2\( \sqrt{2} \)

The surface area of a cylinder is 2πr² + 2πrh:

sa = 2πr² + 2πrh
sa = 2π(9²) + 2π(9 x 5)
sa = 2π(81) + 2π(45)
sa = (2 x 81)π + (2 x 45)π
sa = 162π + 90π
sa = 252π

The volume of a cube is height x length x width:

v = h x l x w
v = 9 x 9 x 2
v = 162

A monomial contains one term, a binomial contains two terms, and a polynomial contains more than two terms.

A trapezoid is a quadrilateral with one set of parallel sides.