Miscellaneous
Slope of a line
(y2 − y1)/(x2 − x1)
Mode
value in the list that appears most often
Area of a triangle
(1/2)bh
(xa)(xb)=
xa+b
Prime Number
Any number that is only divisible by 1 or itself.
What is the relationship between x and y if y=kx
Y is directly proportional to x
Median
middle value in the list (which must be sorted)
Circumference
Circumference = 2πr
xa/xb
xa-b
In similar triangles, corresponding ____ are equal and corresponding _____ are proportional
Corresponding angles are equal; corresponding sides are proportional
What is the relationship between x and y if y=k/x
Y is inversely proportional to x
Average
sum of terms/number of terms
Volume of a cylinder
Volume = πr2h
a2 − 2ab + b2=
(a − b)(a − b)
The sequence t1, t1 + d, t1 + 2d is what type of sequence?
Ex. 3,7,11,11
Arithmetic
Area of a Parallelogram
Area=lh
Probability
number of desired outcomes/number of total outcomes
Length of an Arc (Degrees)
(n◦/360◦) · 2πr
sqrt(xy)=
sqrt(x) · sqrt(y)
The sequence t1, t1 · r, t1 · r2 is what type of sequence (Ex. 3, 6, 12, 24)
Geometric
Perpendicular lines have ______ slopes; Parallel lines have ______ slopes
Perpendicular lines have negative reciprocal slopes; Parallel lines have equal slopes
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.
Sides of a 30, 60, 90 triangle
x, x((sqrt)3), 2x
1/xb=
x-b
Function
For any given value of x, there can only be one corresponding value of y