SAT Math Formulas

Memorize this for the math DSAT

Slope

(y2-y1)/(x2-x1)

Perpendicular Slope

(a/b) →(-b/a)

Slope intercept

y=mx+b

Point Slope

y-y1=m(x-x1)

Inequalities

Treat them like equal signs until finished. Flip the sign when multiplying or dividing by a negative

Quadratic formula

x=(-b+-√b²-4ac)/2a

Vertex form

y=a(x-h)²+k

Sum of solutions

-b/a

Product of solutions

c/a

Discriminant

b²-4ac

Squaring a binomial

(a+b)²=a²+2ab+b²

Difference of squares

a²-b²=(a+b)(a-b)

Midpoint formula

((x1+x2)/2,(y1+y2)/2)

Distance formula

√(x2-x1)²+(y2-y1)²

Probability

(# of desired outcomes)/(# of possible outcomes)

Rates

Distance=rate*time

Arc Length

L= (n/360)2πr

Circle Equation

(x-h)²+(y-k)²=r²

What does h and k represent in a circle equation

(h,k) the center of the circle

Pythagorean Theorem

a²+b²=c²

Sin and Cos Property

sin(x)=cos(90-x)

45 45 90 triangle

a, a, a√2

30 60 90 triangle

a, a√3, 2a

Area of an equilateral triagle

(s²√3)/4

Pythagorean tripes and their multiples

(3,4,5)(5,12,13)(7,24,25)(8,15,17)

Sum of interiror angles

s=(n-2)180