SAT Math Formulas and Facts

Miscellaneous

100

Slope of a line

(y₂ − y₁)/(x₂ − x₁)

200

What is the relationship between x and y if y=kx

Y is directly proportional to x

300

What is the relationship between x and y if y=k/x

Y is inversely proportional to x

400

Area of a Parallelogram

Area=lh

500

Perpendicular lines have ______ slopes; Parallel lines have ______ slopes

Perpendicular lines have negative reciprocal slopes; Parallel lines have equal slopes

Statistics & Probability

100

Mode

value in the list that appears most often

200

Median

middle value in the list (which must be sorted)

300

Average

sum of terms/number of terms

400

Probability

number of desired outcomes/number of total outcomes

500

Fundamental Counting Principle

If an event can happen in N ways, and another, independent event can happen in M ways, then both events together can happen in N x M ways.

Geometry

100

Area of a triangle 

(1/2)bh

200

Circumference 

Circumference = 2πr

300

Volume of a cylinder

Volume = πr²h

400

Length of an Arc (Degrees)

(n◦/360◦) · 2πr

500

Sides of a 30, 60, 90 triangle

x, x((sqrt)3), 2x

Powers, Exponents, Roots, and Factoring

100

(x^a)(x^b)=

x^a+b

200

x^a/x^b

x^a-b

300

a² − 2ab + b²=

(a − b)(a − b)

400

sqrt(xy)=

sqrt(x) · sqrt(y)

500

1/x^b=

x^-b

Definitions

100

Prime Number

Any number that is only divisible by 1 or itself. 

200

In similar triangles, corresponding ____ are equal and corresponding _____ are proportional

Corresponding angles are equal; corresponding sides are proportional

300

The sequence t1, t1 + d, t1 + 2d is what type of sequence? 

Ex. 3,7,11,11

Arithmetic

400

The sequence t1, t1 · r, t1 · r² is what type of sequence (Ex. 3, 6, 12, 24) 

Geometric

500

Function

For any given value of x, there can only be one corresponding value of y