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:

(y + 9)(y + 6)
(y x y) + (y x 6) + (9 x y) + (9 x 6)
y² + 6y + 9y + 54
y² + 15y + 54

A line segment is a portion of a line with a measurable length. The midpoint of a line segment is the point exactly halfway between the endpoints. The midpoint bisects (cuts in half) the line segment.

Perimeter is equal to the sum of the four sides:

p = a + b + c + d
p = 2 + 6 + 6 + 7
p = 21

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 - 6 < 7 - 9a
-5a < 7 - 9a + 6
-5a + 9a < 7 + 6
4a < 13
a < \( \frac{13}{4} \)
a < 3\(\frac{1}{4}\)

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 2) + (2 x 2 x 7) + (2 x 7 x 7)
sa = (28) + (28) + (98)
sa = 154