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

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 (c) on one side of the equation and put everything else on the other side.

9c - 8z = -7c + 7z + 2
9c = -7c + 7z + 2 + 8z
9c + 7c = 7z + 2 + 8z
16c = 15z + 2
c = \( \frac{15z + 2}{16} \)
c = \( \frac{15z}{16} \) + \( \frac{2}{16} \)
c = \(\frac{15}{16}\)z + \(\frac{1}{8}\)

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. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).

The Pythagorean theorem defines the relationship between the side lengths of a right triangle. The length of the hypotenuse squared (c²) is equal to the sum of the two perpendicular sides squared (a² + b²): c² = a² + b² or, solved for c, \(c = \sqrt{a + b}\)