A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).

A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r²h and the surface area is 2(π r²) + 2π rh.

To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.

(8a)(6ab) + (6a²)(9b)
(8 x 6)(a x a x b) + (6 x 9)(a² x b)
(48)(a¹⁺¹ x b) + (54)(a²b)
48a²b + 54a²b
102a²b

The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:

b² - 3b - 58 = -2b - 2
b² - 3b - 58 + 2 = -2b
b² - 3b + 2b - 56 = 0
b² - b - 56 = 0

Next, factor the quadratic equation:

b² - b - 56 = 0
(b + 7)(b - 8) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (b + 7) or (b - 8) must equal zero:

If (b + 7) = 0, b must equal -7
If (b - 8) = 0, b must equal 8

So the solution is that b = -7 or 8

The formula for circumference is circle diameter x π. Circle diameter is 2 x radius:

c = πd
c = π(2 * r)
c = π(2 * 6)
c = 12π