To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses.

The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:

y² - 10y + 16 = 0
(y - 2)(y - 8) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (y - 2) or (y - 8) must equal zero:

If (y - 2) = 0, y must equal 2
If (y - 8) = 0, y must equal 8

So the solution is that y = 2 or 8

To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the > sign and the answer on the other.

-9c + 6 > 7 + 4c
-9c > 7 + 4c - 6
-9c - 4c > 7 - 6
-13c > 1
c > \( \frac{1}{-13} \)
c > -\(\frac{1}{13}\)

To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce -45 as well and sum (Inside, Outside) to equal -4. For this problem, those two numbers are -9 and 5. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² - 4y - 45
y² + (-9 + 5)y + (-9 x 5)
(y - 9)(y + 5)

The volume of a cylinder is πr²h:

v = πr²h
v = π(4² x 1)
v = 16π