Area of a triangle

1/2 base x height

Area of a circle

pi x r²

Surface Area of a prism/box

2lw +2lh + 2wh

Volume of a cylinder

pi x r² x h

Volume of a prism/box

l x w x h

Area of a parallelogram

base x height

Surface area of a cube

6s²

Circumference of a circle

pi x diameter

Degrees in a triangle

180

Degrees in a circle

360

Degrees in a quadrilateral

360

Complementary angles

Add to 90 degrees

Supplementary angles

Add to 180 degrees

Interior angles of an equilateral triangle

60 degrees

Acute angles

Less than 90 degrees

Obtuse angles

Greater than 90 degrees

Pythagorean Theorem

a² + b² = c²

Perimeter

2L + 2W (quadrilaterals)

or

add the length of each side of the shape

Isosceles Triangle

Two legs/sides are the same length.

The third leg/side is a different length.