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 equal sign and the answer on the other.

7y + 9 = 7 + 6y
7y = 7 + 6y - 9
7y - 6y = 7 - 9
y = -2

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(3 + 2)(3)
a = ½(5)(3)
a = ½(15) = \( \frac{15}{2} \)
a = 7\(\frac{1}{2}\)

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 + 4)(y + 2)
(y x y) + (y x 2) + (4 x y) + (4 x 2)
y² + 2y + 4y + 8
y² + 6y + 8

The coordinate grid is composed of a horizontal x-axis and a vertical y-axis. The center of the grid, where the x-axis and y-axis meet, is called the origin.

A rhombus is a parallelogram with four equal-length sides. A square is a rectangle with four equal-length sides.