original from istree - Modified by Drue Gawel
289653868 | quadratic formula | x = [-b ± √(b² - 4ac)] / (2a) for the equation ax²+bx+c= 0 | |
289653869 | slope formula | m = (y₂- y₁) / (x₂- x₁) | |
289653870 | rationals | fractions (anything expressible as a ratio of integers) | |
289653871 | order of operations | PEMDAS (Parentheses (grouping symbols - inside to outside) / Exponents / Multiply & Divide (Left to right) / Add & Subtract (Left to right)) | |
289653872 | Arithmetic Sequences | t₁, t₁+ d, t₁+2d, ... | |
289653873 | Geometric Sequences | t₁, t₁· r, t₁· r², ... | |
289653874 | percentages | part = (percent / 100) x whole; is/of=%/100 | |
289653875 | average or mean | sum of terms / number of terms | |
289653876 | average speed | total distance / total time | |
289653877 | sum | (the average of a group of number) x (number of terms) | |
289653878 | mode | value in the list that appears most often | |
289653879 | median | middle value in the list after values are put in numerical order. If there are two numbers in the middle - take their average. | |
289653880 | 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. | |
289653881 | probability | number of desired outcomes / number of total outcomes | |
289653882 | x^a · x^b = | x^a · x^b = x^(a+b) | |
289653883 | x^a / x^b = | x^a / x^b = x^(a-b) | |
289653884 | 1 / x^b = | 1 / x^b = x^(-b) | |
289653885 | (x^a)^b = | (x^a)^b = x^(a·b) | |
289653886 | x^0 | 1 | |
289653887 | √(xy) | √(xy) = √x · √y | |
289653888 | FOIL | (x+a)(x+b) = x² + (b+a)x + ab | |
289653889 | difference of squares | a² -b² = (a+b)(a-b) | |
289653890 | a² + 2ab + b² | (a+b)² | |
289653891 | a² - 2ab + b² | (a-b)(a-b) | |
289653892 | distance formula | √[(x₂- x₁)² + (y₂- y₁)²)] | |
289653893 | midpoint formula | ((x₁+ x₂)/2 , (y₁+ y₂)/2) | |
289653894 | intersecting lines | opposite angles are equal (each pair of angles along the same line add to 180 degrees) | |
289653895 | area of triangle | area = (bh)/ 2 | |
289653896 | angles of triangle | add up to 180 degrees | |
289653897 | length of triangle sides | length of 1 side is always less than the sum of the other 2 | |
289653898 | equilateral | three equal sides, all angles = 60 degrees (three equal angles) | |
289653899 | isosceles | 2 equal sides, 2 equal angles | |
289653900 | similar | same shape, corresponding angles are equal, corresponding sides are in proportion | |
289653901 | full circle | = 360 degrees | |
289653902 | length of arc | = angle (in degrees) / 360° * 2 π r ; OR = r * angle (in radians) | |
289653903 | rectangle area | length * width | |
289653904 | parallelogram area | base * height | |
289653905 | rectangular solid volume | length * width * height | |
289653906 | right cylinder volume | pi · r² · h | |
289653907 | equation of circle | (x - h)² + (y - k)² = r² ; (h,k) is the center | |
289653908 | logarithms | y = log(little b)x means b^y = x | |
289653909 | complex numbers | a + bi | |
289653910 | special sin cos relationship | sin²(angle) + cos²(angle) = 1 | |
289653911 | trapezoid area | [(base₁ + base₂) / 2] · h | |
289653912 | direct variation | y=kx | |
289653913 | inverse variation | y=k/x | |
289653914 | slope-intercept form | y=mx+b | |
289653915 | point-slope form | y - y1= m(x - x1) | |
289653916 | standard form | Ax + By=C, where A, B, and C are not decimals or fractions, where A and B are not both zero, and where A is not a negative | |
289653917 | Dividing by a negative number in an inequality | must reverse the inequality symbol | |
289653918 | Graphing < or > on a coordinate plane | dotted line | |
289653919 | Graphing ≥ or ≤ on a coordinate plane | solid line | |
289653920 | Graphing ≥ or > on a coordinate plane | shade upwards or to the right | |
289653921 | Graphing ≤ or < on a coordinate plane | shade downwards or to the left | |
289653922 | chord | The distance from one point on the circle to another point on the circle. | |
289653923 | sector | The part of a circle that looks like a piece of pie. A sector is bounded by 2 radii and an arc of the circle. | |
289653924 | arc | Part of a circle connecting two points on the circle; could be minor (less than 180 degrees - needs 2 letters to name it) or major (greater than or equal to 180 degrees - needs 3 letters to name it) | |
289653925 | Central Angle | An angle whose vertex is the center of the circle; equal to the degree measurement of the intercepted arc it creates | |
289653926 | Pythagorean Theorem | a²+b²=c² (c=hypotenuse, only true for right triangles) | |
289653927 | Slope formula [between 2 points (x₁,y₁) and (x₂, y₂)] | y2 - y1/ x2-x1 | |
289653928 | Logarithm Formula: log base x = y | b to the y power equals x | |
289653929 | sin | =opposite/hypotenuse (this is the 'SOH" in SOHCAHTOA) | |
289653930 | cos | =adjacent/hypotenuse (this is the 'CAH" in SOHCAHTOA) | |
289653931 | tan | opposite/adjacent (this is the 'TOA" in SOHCAHTOA) | |
289653934 | FOIL | First, Outer, Inner, Last | |
289653935 | Number of degrees in n-sided polygon | (n-2)(180) | |
289653936 | Percent Formula | is/of = %/100 | |
289653938 | adjacent angles | are a pair of angles with a common vertex and a common side, but no common interior points | |
289653939 | area | the number of square units needed to cover a flat surface | |
289653940 | circle | a plane figure made up of all the points the same distance from the center. | |
289653941 | circumference | the distance around a circle; C = 2*pi*r; C = pi * d | |
289653942 | complementary angles | two angles whose sum is a right angle (90 degrees) | |
289653943 | cube | a three-dimensional shape with six square sides | |
289653944 | diameter | the length of a straight line passing through the center of a circle and connecting two points on the circumference | |
289653945 | equilateral triangle | A triangle with all sides congruent (and all angles congruent). | |
289653937 | acute angle | an angle less than 90 degrees but more than 0 degrees | |
295882998 | right angle | an angle whose measure is 90° | |
289653946 | obtuse angle | an angle between 90 and 180 degrees | |
289653947 | parallel lines defined | coplanar lines that do not intersect | |
289653948 | parallelogram | a quadrilateral whose opposite sides are both parallel and equal in length | |
289653949 | perpendicular lines defined | Two lines that intersect to form right angles | |
289653950 | polygon | a closed plane figure bounded by straight sides | |
289653951 | quadrilateral | a four-sided polygon | |
289653952 | right triangle | a triangle with one right angle | |
289653953 | supplementary angles | Two angles whose sum is 180 degrees | |
289653954 | volume | the amount of 3-dimensional space occupied by an object | |
289653955 | Area of a square | A=side² | |
289653956 | Area of a circle | A=πr² | |
289653957 | Volume of a cube | V=s³ | |
289653958 | Fahrenheit to Celsius | C = 5/9 (F-32) | |
289653959 | Celsius to Fahrenheit | F= 9/5 (C+32) | |
289653960 | The Difference of Two Cubes: a³-b³ = | a³-b³ = (a-b)(a²+ab+b²) | |
289653961 | The Sum of Two Cubes: a³+b³ = | a³+b³ = (a+b)(a²-ab+b²) | |
289653962 | what kind of line has undefined slope | vertical line | |
289653963 | what kind of line has zero slope | horizontal line | |
289653964 | Infinitely many solutions | when the system of equations has the same slope and y-intercept | |
289653965 | One solution | when the system of equations has different slopes and possibly the same y-intercept | |
289653966 | No solution | when the system of equations has the same slope but different y-intercepts | |
289653967 | Elimination method | solving systems by adding or subtracting equations to eliminate a variable (sometimes requires that one or both equations be multiplied by a LCM) | |
289653968 | Solution of the system of linear equations | Any ordered pair in a system that makes is a solution of each equation. | |
289653969 | Graphing method for solving a system of equations | Graphing the system of equations and finding the point at which they intersect | |
289653970 | Substitution method | Replacing one variable with an equivalent expression containing the other variable | |
289653971 | Absolute value equation | A V-shaped graph that points upward or downward | |
289653972 | translation | transformation of a graph that is a shift of a graph horizontally, vertically, or both, which results in a graph of the same shape and size, but in a different position. | |
289653973 | Area of a sector | x°/360° times (πr²), where x is the degrees in the angle | |
289653974 | Radius (Radii) | A segment connecting the center of a circle to any point on the circle | |
289653975 | Sn=n(a₁+an/2) | sum of an arithmetic series | |
289653976 | An=a1+(n-1)d | nth term of a arithmetic series | |
289653977 | An=a₁*r^(n-1) | nth term of a geometric series | |
289653978 | Sn=a₁*(1-r^n)/(1-r) | geometric series sum | |
289653979 | S=a₁/(1-r) | geometric infinite sum ( |r| must be less than 1) | |
289653980 | reflection | transformation resulting in a mirror image over a particular line (usually the x-axis or y-axis) | |
289653981 | dilation | transformation that changes the size of a graph (stretch or compress) | |
289653982 | rotation | transformation that "spins" a graph around a particular point | |
289653983 | parabola | the graph of a quadratic equation | |
289653984 | cosecant (x) = | csc (x) = 1 / sin(x) | |
289653985 | secant (x) = | sec (x) = 1 / cos(x) | |
289653986 | cotangent (x) = | cot = 1 / tan (x) | |
289653987 | y=asin(b*theta) | a: amplitude; b: # of cycles from 0 to 2pi; period: 2pi/b; starts at zero | |
289653988 | y=acos(b*theta) | a: amplitude; b: # of cycles from 0 to 2pi; period: 2pi/b; starts at max | |
289653989 | Law of Cosines | c² = a² + b² - 2abcosC where C is the angle across from side c. Use to find the third side of a triangle when you know two sides and their enclosed angle (SAS) OR Use to find any angle of a triangle when you know all three sides of the triangle (SSS). | |
289653990 | Law of Sines | sinA / a = sinB / b = sinC / c; used with AAS or ASA or SSA. (SSA may yield two possible results if A is acute) | |
289653991 | 45°-45°-90° triangle | hypotenuse = √2 * leg | |
289653992 | 30°-60°-90° triangle | hypotenuse = 2 * shorter leg; longer leg = √3 * shorter leg | |
289653993 | to convert from radians to degrees | multiply by 180/pi | |
289653994 | to convert from degrees to radians | multiply by pi/180 | |
289653995 | an angle with a vertex on a circle | creates an intercepted arc that is twice the degree of that angle | |
295912072 | parallel lines (how do their slopes relate) | parallel lines have the same slope | |
295913207 | perpendicular lines (how do their slopes relate) | perpendicular lines have slopes that are the opposite and reciprocal of one another (e.g. 2/3 and -3/2) |