The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)² : a = π r².

To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce 1 as well and sum (Inside, Outside) to equal 2. For this problem, those two numbers are 1 and 1. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² + 2y + 1
y² + (1 + 1)y + (1 x 1)
(y + 1)(y + 1)

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

a = l x w
a = a x b
a = 5 x 6
a = 30

The slope-intercept equation for a line is y = mx + b where m is the slope and b is the y-intercept of the line. From the graph, you can see that the y-intercept (the y-value from the point where the line crosses the y-axis) is 0. The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, -1) and (2, 1) so the slope becomes:

Plugging these values into the slope-intercept equation:

y = \(\frac{1}{2}\)x + 0

An acute angle measures less than 90°, a right angle measures 90°, and an obtuse angle measures more than 90°.