SAT Math

slope intercept form

y=mx+b

parallel lines

zero solutions

perpendicular lines

one solution

overlapping lines

infinite solutions

standard form

ax² + bx + c

constant in standard form

c

vertex form

y = a(x-h)² + k

coordinates of the vertex in vertex form

(h,k)

quadratic formula

x = (-b ± √(b² - 4ac)) / 2a

sum of solutions (quadratic)

-b/a

product of solutions (quadratic)

c/a

discriminant formula

b² - 4ac

(b² - 4ac) = 0

one solution

(b² - 4ac) > 0

two solutions

(b² - 4ac) < 0

no real solutions

formula for x coordinate of the vertex (from quadratic)

-b / 2a

percent change formula

(new value - old value) / old value x 100

exponential growth formula

f(x) = A (1+r)^t

exponential decay formula

f(x) = A (1-r)^t

even functions

unchanged when reflected over y-axis

odd functions

unchanged when rotated 180^o

mean formula

total sum / number of items

total sum formula

mean * number of items

radian - degree conversion formula

π = 180^o

circle equation

(x-h)² + (y-k)² = r²

(h,k) in circle equation

center of circle

r in circle equation

radius

cos to sine conversion

cos θ = sin (90 - θ)

sine to cos conversion

sin θ = cos (90 - θ)

sin²x + cos²x

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