A quadrilateral is a shape with four sides. The perimeter of a quadrilateral is the sum of the lengths of its four sides.

The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:

a² - 9a + 12 = -2a + 2
a² - 9a + 12 - 2 = -2a
a² - 9a + 2a + 10 = 0
a² - 7a + 10 = 0

Next, factor the quadratic equation:

a² - 7a + 10 = 0
(a - 2)(a - 5) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (a - 2) or (a - 5) must equal zero:

If (a - 2) = 0, a must equal 2
If (a - 5) = 0, a must equal 5

So the solution is that a = 2 or 5

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.

6b + 7z = -2b + 5z - 6
6b = -2b + 5z - 6 - 7z
6b + 2b = 5z - 6 - 7z
8b = -2z - 6
b = \( \frac{-2z - 6}{8} \)
b = \( \frac{-2z}{8} \) + \( \frac{-6}{8} \)
b = -\(\frac{1}{4}\)z - \(\frac{3}{4}\)

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).

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.