Pythagorean Theorem
a2 + b2 = c2, where a and b are the lengths of the legs of a right triangle, and c is the length of the hypotenuse.
Area of a Triangle
Area =
bh, where
b is the length of the base and
h is height.
Sum of the Interior Angles of a Polygon
The sum of the interior angles of a polygon is (n – 2)180°, where n is the number of sides in the polygon.
Area of a Trapezoid
Area =
h, where
s1 and
s2 are the lengths of the bases of the trapezoid, and
h is the height.
Area of a Parallelogram, Rectangle, and Rhombus
Area = bh, where b is the length of the base, and h is the height.
Area of a Square
Area = s2, where s is the length of a side of the square.
Circumference of a Circle
Circumference = 2πr, where r is the radius of the circle.
Arc Length
Arc Length =
2π
r, where
n is the measure of the degree of the arc, and
r is the radius of the circle.
Area of a Circle
Area = πr2, where r is the radius of the circle.
Area of a Sector
Area of Sector =
π
r2, where
n is the measure of the central angle which forms the boundary of the sector, and
r is the radius of the circle.