To solve this equation, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)

-6c(c - z)
-6(9)(9 - 7)
-6(9)(2)
(-54)(2)
-108

The surface area of a cube is (2 x length x width) + (2 x width x height) + (2 x length x height):

sa = 2lw + 2wh + 2lh
sa = (2 x 4 x 9) + (2 x 9 x 3) + (2 x 4 x 3)
sa = (72) + (54) + (24)
sa = 150

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 - b - 32 = b + 3
b² - b - 32 - 3 = b
b² - b - b - 35 = 0
b² - 2b - 35 = 0

Next, factor the quadratic equation:

b² - 2b - 35 = 0
(b + 5)(b - 7) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (b + 5) or (b - 7) must equal zero:

If (b + 5) = 0, b must equal -5
If (b - 7) = 0, b must equal 7

So the solution is that b = -5 or 7

The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)² : a = π r².

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

sa = 2πr² + 2πrh
sa = 2π(3²) + 2π(3 x 1)
sa = 2π(9) + 2π(3)
sa = (2 x 9)π + (2 x 3)π
sa = 18π + 6π
sa = 24π