sat math formulas

growth rate q

present=past(1+growth rate)^t/n

n> the time

what happens when you:

add or subtract all numbers in the data set

multiply or divide all numbers in the data set

mean, median and mode changes

everything chnages

avg/ mean

sum/number

what makes a odd/ even function

odd> f(-x)=-f(x)

even> f(-x)=f(x)

perpendicular line

neg reciprocal slope

of=

is=

of= multiplication

is= equals

exponent rules:

x^a*x^b

x^a/x^b

x^a*x^b=x^a+b

x^a/x^b=x^a-b

interor angles for any shape

180(n-2)

density=

D=M/V

% eq

final=intial (1plusorminus p/100)^t

midpoint formula

(x1-x2)/2

range

largest #-smallest#

Standard deviation

data is scrunched together (even if there are outliers) = SD is low

rational vs irrational vs integer

rational is any number and fractions

irrational is like pi

integer is any whole number positive or negative including 0

increasing x by 30%

decreasing x by 30%

increasing= 1.3x

decreasing= .7x

find slope of tangent line

1) find center and the point where we want the tangent line (h,k) and (x,y)

2) (k-y)/(h-x)

3) ^negative reciprocal of that

inscribed angle theorem

<ABC=1/2<AOB

<ABC=1/2arcAB

what is a tangent line

a line that only hits a fucntion once

a line that hits a circle only at one point so its 180 @ that point

quadratic formula(vertex and standard)

ax²+bx+x=0

y=a(x-h)²+k

midpoint

((x₁ + x₂)/2, (y₁ + y₂)/2) or -b/2a

sum and prod of quadratic solutions

-b/a or c/a

sin and cos relationship

sin=cos(90-x)

cos=sin(90-x)

what does doubling side length do to area and volume

x² turns into 4x²

x³ turns into 8x³

x is length

discriminant

b²-4ac=x

x>0 two solutions (irrational/ rational)

x=0 one solution (rational)

x<0 no solution

quadratic formula x=

x=(-b plusorminus sqrt b²-4ac)/2a

circle formula

arc length

s = (θ/360) * 2πr where s is the arc length, θ is the central angle in degrees, and r is the radius. 

sector area

A = (θ/360) * πr² where A is the sector area, θ is the central angle in degrees, and r is the radius.