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

a = l x w
a = a x b
a = 1 x 5
a = 5

A line on the coordinate grid can be defined by a slope-intercept equation: y = mx + b. For a given value of x, the value of y can be determined given the slope (m) and y-intercept (b) of the line. The slope of a line is change in y over change in x, \({\Delta y \over \Delta x}\), and the y-intercept is the y-coordinate where the line crosses the vertical y-axis.

To solve this equation, isolate the variable for which you are solving (b) on one side of the equation and put everything else on the other side.

4b - 6y = -9b - 2y - 6
4b = -9b - 2y - 6 + 6y
4b + 9b = -2y - 6 + 6y
13b = 4y - 6
b = \( \frac{4y - 6}{13} \)
b = \( \frac{4y}{13} \) + \( \frac{-6}{13} \)
b = \(\frac{4}{13}\)y - \(\frac{6}{13}\)

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