Questions | 5 |

Topics | Dimensions, Quadrilateral, Rectangle & Square, Slope-Intercept Equation, Two Variables |

A circle is a figure in which each point around its perimeter is an equal distance from the center. The **radius** of a circle is the distance between the center and any point along its perimeter (AC, CB, CD). A **chord** is a line segment that connects any two points along its perimeter (AB, AD, BD). The **diameter** of a circle is the length of a chord that passes through the center of the circle (AB) and equals twice the circle's radius (2r).

A quadrilateral is a shape with four sides. The **perimeter** of a quadrilateral is the sum of the lengths of its four sides (a + b + c + d).

A rectangle is a parallelogram containing four right angles. Opposite sides (a = c, b = d) are equal and the perimeter is the sum of the lengths of all sides (a + b + c + d) or, comonly, 2 x length x width. The area of a rectangle is length x width. A **square** is a rectangle with four equal length sides. The perimeter of a square is 4 x length of one side (4s) and the area is the length of one side squared (s^{2}).

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.

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, **P**arentheses, **E**xponents, **M**ultiplication/**D**ivision, **A**ddition/**S**ubtraction.)