GREq

Area of a Trapezoid

(Base1 + Base2)/2 * h

Degrees of a polygon

180(n-2)

Degree measure of a congruent polygon

(180*(n-2))/n

Area of a circle

𝛑r²

Circumference of a circle

2𝛑r

Arc Length of a circle

x/360 × 2𝛑r

angle/360*circumference

Area of a sector of a circle

x/360 * 𝛑r²

angle/360*area

Combinations

nCr = n! / r!(n-r)!

Combinations are where order doesn’t matter, just inclusion

Permutations

nPr = n!/(n-r)!

Permutations are the one where you want to find every single possible combination

Percent Change

new - old / old * 100

Simple Interest Rate

V = P(1+(rt/100))

Compound Interest Rate

V = P(1+r/100n)^nt

Distance

sqrt((x₂-x₁)²+(y₂-y₁)²)