The area of a rectangle is equal to its length x width:

a = l x w
a = a x b
a = 8 x 2
a = 16

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 -30 as well and sum (Inside, Outside) to equal 1. For this problem, those two numbers are -5 and 6. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² + y - 30
y² + (-5 + 6)y + (-5 x 6)
(y - 5)(y + 6)

When solving an equation with two variables, 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.)

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.

-5a + 1 > -4 + 5a
-5a > -4 + 5a - 1
-5a - 5a > -4 - 1
-10a > -5
a > \( \frac{-5}{-10} \)
a > \(\frac{1}{2}\)

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 7 x 7) + (2 x 7 x 9) + (2 x 7 x 9)
sa = (98) + (126) + (126)
sa = 350