AP Notes, Outlines, Study Guides, Vocabulary, Practice Exams and more!

ACT Math Cards Flashcards

original from istree - Modified by Drue Gawel

Terms : Hide Images
289653868quadratic formulax = [-b ± √(b² - 4ac)] / (2a) for the equation ax²+bx+c= 0
289653869slope formulam = (y₂- y₁) / (x₂- x₁)
289653870rationalsfractions (anything expressible as a ratio of integers)
289653871order of operationsPEMDAS (Parentheses (grouping symbols - inside to outside) / Exponents / Multiply & Divide (Left to right) / Add & Subtract (Left to right))
289653872Arithmetic Sequencest₁, t₁+ d, t₁+2d, ...
289653873Geometric Sequencest₁, t₁· r, t₁· r², ...
289653874percentagespart = (percent / 100) x whole; is/of=%/100
289653875average or meansum of terms / number of terms
289653876average speedtotal distance / total time
289653877sum(the average of a group of number) x (number of terms)
289653878modevalue in the list that appears most often
289653879medianmiddle value in the list after values are put in numerical order. If there are two numbers in the middle - take their average.
289653880fundamental counting principleif 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.
289653881probabilitynumber of desired outcomes / number of total outcomes
289653882x^a · x^b =x^a · x^b = x^(a+b)
289653883x^a / x^b =x^a / x^b = x^(a-b)
2896538841 / x^b =1 / x^b = x^(-b)
289653885(x^a)^b =(x^a)^b = x^(a·b)
289653886x^01
289653887√(xy)√(xy) = √x · √y
289653888FOIL(x+a)(x+b) = x² + (b+a)x + ab
289653889difference of squaresa² -b² = (a+b)(a-b)
289653890a² + 2ab + b²(a+b)²
289653891a² - 2ab + b²(a-b)(a-b)
289653892distance formula√[(x₂- x₁)² + (y₂- y₁)²)]
289653893midpoint formula((x₁+ x₂)/2 , (y₁+ y₂)/2)
289653894intersecting linesopposite angles are equal (each pair of angles along the same line add to 180 degrees)
289653895area of trianglearea = (bh)/ 2
289653896angles of triangleadd up to 180 degrees
289653897length of triangle sideslength of 1 side is always less than the sum of the other 2
289653898equilateralthree equal sides, all angles = 60 degrees (three equal angles)
289653899isosceles2 equal sides, 2 equal angles
289653900similarsame shape, corresponding angles are equal, corresponding sides are in proportion
289653901full circle= 360 degrees
289653902length of arc= angle (in degrees) / 360° * 2 π r ; OR = r * angle (in radians)
289653903rectangle arealength * width
289653904parallelogram areabase * height
289653905rectangular solid volumelength * width * height
289653906right cylinder volumepi · r² · h
289653907equation of circle(x - h)² + (y - k)² = r² ; (h,k) is the center
289653908logarithmsy = log(little b)x means b^y = x
289653909complex numbersa + bi
289653910special sin cos relationshipsin²(angle) + cos²(angle) = 1
289653911trapezoid area[(base₁ + base₂) / 2] · h
289653912direct variationy=kx
289653913inverse variationy=k/x
289653914slope-intercept formy=mx+b
289653915point-slope formy - y1= m(x - x1)
289653916standard formAx + 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
289653917Dividing by a negative number in an inequalitymust reverse the inequality symbol
289653918Graphing < or > on a coordinate planedotted line
289653919Graphing ≥ or ≤ on a coordinate planesolid line
289653920Graphing ≥ or > on a coordinate planeshade upwards or to the right
289653921Graphing ≤ or < on a coordinate planeshade downwards or to the left
289653922chordThe distance from one point on the circle to another point on the circle.
289653923sectorThe part of a circle that looks like a piece of pie. A sector is bounded by 2 radii and an arc of the circle.
289653924arcPart 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)
289653925Central AngleAn angle whose vertex is the center of the circle; equal to the degree measurement of the intercepted arc it creates
289653926Pythagorean Theorema²+b²=c² (c=hypotenuse, only true for right triangles)
289653927Slope formula [between 2 points (x₁,y₁) and (x₂, y₂)]y2 - y1/ x2-x1
289653928Logarithm Formula: log base x = yb to the y power equals x
289653929sin=opposite/hypotenuse (this is the 'SOH" in SOHCAHTOA)
289653930cos=adjacent/hypotenuse (this is the 'CAH" in SOHCAHTOA)
289653931tanopposite/adjacent (this is the 'TOA" in SOHCAHTOA)
289653934FOILFirst, Outer, Inner, Last
289653935Number of degrees in n-sided polygon(n-2)(180)
289653936Percent Formulais/of = %/100
289653938adjacent anglesare a pair of angles with a common vertex and a common side, but no common interior points
289653939areathe number of square units needed to cover a flat surface
289653940circlea plane figure made up of all the points the same distance from the center.
289653941circumferencethe distance around a circle; C = 2*pi*r; C = pi * d
289653942complementary anglestwo angles whose sum is a right angle (90 degrees)
289653943cubea three-dimensional shape with six square sides
289653944diameterthe length of a straight line passing through the center of a circle and connecting two points on the circumference
289653945equilateral triangleA triangle with all sides congruent (and all angles congruent).
289653937acute anglean angle less than 90 degrees but more than 0 degrees
295882998right anglean angle whose measure is 90°
289653946obtuse anglean angle between 90 and 180 degrees
289653947parallel lines definedcoplanar lines that do not intersect
289653948parallelograma quadrilateral whose opposite sides are both parallel and equal in length
289653949perpendicular lines definedTwo lines that intersect to form right angles
289653950polygona closed plane figure bounded by straight sides
289653951quadrilaterala four-sided polygon
289653952right trianglea triangle with one right angle
289653953supplementary anglesTwo angles whose sum is 180 degrees
289653954volumethe amount of 3-dimensional space occupied by an object
289653955Area of a squareA=side²
289653956Area of a circleA=πr²
289653957Volume of a cubeV=s³
289653958Fahrenheit to CelsiusC = 5/9 (F-32)
289653959Celsius to FahrenheitF= 9/5 (C+32)
289653960The Difference of Two Cubes: a³-b³ =a³-b³ = (a-b)(a²+ab+b²)
289653961The Sum of Two Cubes: a³+b³ =a³+b³ = (a+b)(a²-ab+b²)
289653962what kind of line has undefined slopevertical line
289653963what kind of line has zero slopehorizontal line
289653964Infinitely many solutionswhen the system of equations has the same slope and y-intercept
289653965One solutionwhen the system of equations has different slopes and possibly the same y-intercept
289653966No solutionwhen the system of equations has the same slope but different y-intercepts
289653967Elimination methodsolving systems by adding or subtracting equations to eliminate a variable (sometimes requires that one or both equations be multiplied by a LCM)
289653968Solution of the system of linear equationsAny ordered pair in a system that makes is a solution of each equation.
289653969Graphing method for solving a system of equationsGraphing the system of equations and finding the point at which they intersect
289653970Substitution methodReplacing one variable with an equivalent expression containing the other variable
289653971Absolute value equationA V-shaped graph that points upward or downward
289653972translationtransformation 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.
289653973Area of a sectorx°/360° times (πr²), where x is the degrees in the angle
289653974Radius (Radii)A segment connecting the center of a circle to any point on the circle
289653975Sn=n(a₁+an/2)sum of an arithmetic series
289653976An=a1+(n-1)dnth term of a arithmetic series
289653977An=a₁*r^(n-1)nth term of a geometric series
289653978Sn=a₁*(1-r^n)/(1-r)geometric series sum
289653979S=a₁/(1-r)geometric infinite sum ( |r| must be less than 1)
289653980reflectiontransformation resulting in a mirror image over a particular line (usually the x-axis or y-axis)
289653981dilationtransformation that changes the size of a graph (stretch or compress)
289653982rotationtransformation that "spins" a graph around a particular point
289653983parabolathe graph of a quadratic equation
289653984cosecant (x) =csc (x) = 1 / sin(x)
289653985secant (x) =sec (x) = 1 / cos(x)
289653986cotangent (x) =cot = 1 / tan (x)
289653987y=asin(b*theta)a: amplitude; b: # of cycles from 0 to 2pi; period: 2pi/b; starts at zero
289653988y=acos(b*theta)a: amplitude; b: # of cycles from 0 to 2pi; period: 2pi/b; starts at max
289653989Law of Cosinesc² = 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).
289653990Law of SinessinA / a = sinB / b = sinC / c; used with AAS or ASA or SSA. (SSA may yield two possible results if A is acute)
28965399145°-45°-90° trianglehypotenuse = √2 * leg
28965399230°-60°-90° trianglehypotenuse = 2 * shorter leg; longer leg = √3 * shorter leg
289653993to convert from radians to degreesmultiply by 180/pi
289653994to convert from degrees to radiansmultiply by pi/180
289653995an angle with a vertex on a circlecreates an intercepted arc that is twice the degree of that angle
295912072parallel lines (how do their slopes relate)parallel lines have the same slope
295913207perpendicular 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)

Need Help?

We hope your visit has been a productive one. If you're having any problems, or would like to give some feedback, we'd love to hear from you.

For general help, questions, and suggestions, try our dedicated support forums.

If you need to contact the Course-Notes.Org web experience team, please use our contact form.

Need Notes?

While we strive to provide the most comprehensive notes for as many high school textbooks as possible, there are certainly going to be some that we miss. Drop us a note and let us know which textbooks you need. Be sure to include which edition of the textbook you are using! If we see enough demand, we'll do whatever we can to get those notes up on the site for you!