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

a = l x w
a = a x b
a = 2 x 3
a = 6

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 -35 as well and sum (Inside, Outside) to equal 2. For this problem, those two numbers are -5 and 7. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² + 2y - 35
y² + (-5 + 7)y + (-5 x 7)
(y - 5)(y + 7)

The formula for area is πr². Radius is circle \( \frac{diameter}{2} \):

r = \( \frac{d}{2} \)
r = \( \frac{6}{2} \)
r = 3
a = πr²
a = π(3²)
a = 9π

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.

Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).