Study your flashcards anywhere!
Download the official Cram app for free >
 Shuffle Toggle OnToggle Off
 Alphabetize Toggle OnToggle Off
 Front First Toggle OnToggle Off
 Both Sides Toggle OnToggle Off
 Read Toggle OnToggle Off
How to study your flashcards.
Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key
Up/Down arrow keys: Flip the card between the front and back.down keyup key
H key: Show hint (3rd side).h key
A key: Read text to speech.a key
89 Cards in this Set
 Front
 Back
equilateral triangles

all sides = 60


3rd Side Rule

3rd side must be greater than the difference of the other two and less than the sum of the other two


similar triangles

sides are proportional


Common Triples

3:4:5
5:12:13 

Isoceles Right triangle

454590
sides are 1:1:root2 

306090 triangle

1:root3:2


divisible by 3 or 9

sum of digits must be divisible by 3 or 9


divisible by 4

last 2 digits divisible by 4


divisible by 6

must be divisible by 2 and 3


sq. root of 169

13


sq. root of 196

14


sq. root of 225

15


sq. root of 256

16


sq. root of 625

25


cube root of 64

4


cube root of 125

5


cube root of 216

6


convert 3:4 to a fraction

3 (or 4) / 7


Super Pythag

a^2+b^2+c^2=d^2


angles of a regular polygon add up to

(#sides  2) x 180


Area of a trapezoid

1/2 (b1 +b2)(height)


in comparing the areas of triangles/quadrilaterals, look for

shared bases


Group Formula

if overlap:
A + B + Neither  Both = Total if no overlap: use grid 

Standard Deviation percents

2143434142


0!=

1


1!=

1


Beginning of PENMDAS

Parenthesis, Exponents, Negation


factors of quadratic equation that is (+,+)

(+,+)


factors of quadratic equation that is (,+)

(,)


factors of quadratic equation that is (+,)

biggest is +


factors of quadratic equation that is (,)

biggest is negative


equation of: (x+y)^2

x^2 + 2xy + y^2


factors of: x^2 + 2xy + y^2

(x+y)^2


equation of: (xy)^2

x^2  2xy + y^2


factors of: x^2  2xy + y^2

(xy)^2


equation of: (x+y)(xy)

x^2y^2


factors of: x^2y^2

(x+y)(xy)


(8x)^2

6416x+x^2


Geometric Mean

square root


slope is

change in y
change in x 

equation of a line

y=mx+b


y intercept

x=0


x intercept

y=0


slope>1

closer to y axis


slope<1

closer to x axis


diagonal of a square=

side x root2


diagnal of a square =

side x root2


first prime #

2


"and" probability problems

multiply


"at least" probability problems

1 NOT
(not may be multiplication because "and) 

When order doesn't matter

less discrete elements (small #, placeholders on bottom)


When order does matter

more discrete numbers (bigger, no placeholders)


Interquartiles

divide into 2 groups, take median (Q2);
then divide two groups into two more and take those medians (Q1 and Q3) 

Interquartile range

Q3Q1


square root of 121

11


square root of 144

12


cube root of 8

2


cube root of 27

3


Integer

No decimal or fractions


digits

09 (phone pad)


"distinct"

different (e.g. 2 and 3 are distinct)


9/4

225%


225%

9/4


2.25

9/4


66%

.66666666


66%

2/3


12.5%

1/8


1/8

12.5%


.125

1/8


37.5%

3/8


3/8

37.5%


3/8

.375


62.5%

5/8


5/8

62.5%


5/8

.625


87.5%

7/8


7/8

87.5%


7/8

.875


root 3 means

306090 triangle somewhere


root 2 means

454590 triangle somewhere


perpendicular lines

slopes are negative recipricals (eg. 5 and 1/5)


exponent (trigger)

break into common factors, regroup


root 2=

1.4 (Valentines)


root 3=

1.7 (St. Paddy's)


"part/arc/sector of a circle"

Central angle/360 = arc/circum = sector/area


to find intersection of two lines

1.) set line equations equal to eachother and solve 2.) plug in x into either equation


"combination"

order doesn't matter, #s on bottom


"arrangement"

order does matter


range

difference b/w largest and smallest # in a set
