The area of a trapezoid is one-half the sum of the lengths of the parallel sides multiplied by the height:

a = ½(b + d)(h)
a = ½(7 + 7)(3)
a = ½(14)(3)
a = ½(42) = \( \frac{42}{2} \)
a = 21

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.

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.

z + 9 > 3 + 8z
z > 3 + 8z - 9
z - 8z > 3 - 9
-7z > -6
z > \( \frac{-6}{-7} \)
z > \(\frac{6}{7}\)

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 16 as well and sum (Inside, Outside) to equal 10. For this problem, those two numbers are 2 and 8. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² + 10y + 16
y² + (2 + 8)y + (2 x 8)
(y + 2)(y + 8)

An equation is two expressions separated by an equal sign. The key to solving equations is to repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.