SATs Math Formula

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Slope formula

(y2-y1)/(x2-x1)

Slope-intercept form

y=mx+b

Standard form of Quadratic

ax²+bx+c
a>0 Parabola opens up
a<0 Parabola opens down
c = y-intercept

Factored form of Quadratic

a(x-r)(x-s)=0
r and s are solutions

Vertex @ point (h,k)

y=a(x-h)²+k

Exponential growth formula

y=a(1+r)^t
y= Final total amount after time passes
a= inital starting value
r= Rate of increase (decimal)
t/x=number of time

Exponential decay formula

y=a(1-r)^t
y=Final remaining amount after decrease
a= initial starting value
r= Rate of decrease (decimal)
t/x=number of time

Percent Change Formula

((New Value- Old Value ) / (Old Value)) / x 100

Circle Area Formula

pi r²

Circle Circumference Formula

2pi r

Rectangle Area Formula

length x width

Triangle Area formula

½ x b x h

Pythagorean Theorem

a²+b²=c²
(Triangle must be right triangle)

Volume of rectangular solid

length x width x height

Volume of a cylinder

pi x r² x h

Volume of a sphere formula

4/3 pi r³

Volume of a cone formula

1/3 pi r² h

Volume of a pyramid formula

1/3 x l x w x h

Standard form of a line

Ax+By=C
-A/B = slope
C/B= y-int

Sum of solutions for quadratic formula

-b/a

Product of solutions for quadratic formula

c/a

X-coord of vertex of quadratic formula

-b/ 2a

Discriminant of a Quadratic Formula

D=b² -4ac
D>0 = 2 real solutions
D=0 = 1 real solution
D<0 = No real solution

Mean

Total of all elements / Number of elements

Median

Middle value of terms in consecutive order

Mode

Most common occurring element

Circumference of a circle

pi x diameter

Diameter of a circle

2r

Volume of a cube

s³

Surface area of a sphere

4pi r²

Surface area of right circular cylinder

S = 2πr ² + 2πrh

Surface area of a cube

6s²

Surface area of rectangular solid

2(lw + lh + wh)

Interior angle formula

((n-2)(180 dg))/ n

Polygon Angle Sum Theorem

( (n-2)(180 dg) )/ n

Perimeter of a rectangle

2(l+w)

Area of parallelogram

b x h

Length of arc formula

(2pi x r)( degrees measure center of arc / 360 )

Midpoint formula

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

Standard Circle Equation

(x-h)² + (y-k)² = r²
(h,k)=center of circle

r=radius

Distance Formula

square root of ((x2-x1)² + (y2-y1)²)

Area of an arc sector

(pi x r²)( degrees measure center of arc / 360)

Probability formula

number of desired outcomes/ total number of possible outcomes

1= guaranteed to happen

0 = will never happen

x percent of a given number n

n(x/100)

What percent a number n is of another number m?

(n100)(m)

What number n is x percent of

(n100)/x

Volume-length ratio for similar solids

Volume ratio=(length ratio)³