GRE

 area of triangle 1/2 base x height pythagorean theorem only for right triangles a2 + b2 = c2 right triangle ratios (4) 3:4:55:12:13s : s : s/2s : s/3 : 2s area of square (2) s21/2 d2 d=diagonal area of rhombus, 4 equal sides, 4 angles that aren't necessary right angles 1/2 d1 d2 area of parallelogram 2 opposite and equal pairs of sides base x height area of rapezoid 1/2 (b1 + b2) x h total interior angle (n-2) 180 n=number of sides average measure of one angle in polygon (n-2)180 / n volume of polygon area of the base x height volume of a cylinder (pie r2) height total surface area of a cube 6e2 total surface area of rectangular solid 2(l w) + 2 (w h) + 2 (h l) total surface area of a cylinder (circumference x height) + 2(pie r2) distance between 2 points / (x2 - x1)2 + (y2 - y1)2 circumference of circle 2pie r pie d area of circle pie r2 length of an arc 1. find the circumference of the circle (2pie r, pie d)2. put the degree measure* of the arc over 360, reduce fraction 3. multiply circumference by the fraction area of a sector 1. find area of the circle (r2)2 . put degree measure* of sector over 360, reduce3. multiply the area by the fraction equations for FOIL (a+b)2 = a2 + 2ab + b2 (a-b)2 = a2 - 2ab + b2 (a-b)(a+b) = a2 - b2 find probability number of possible desired outcomes/ number of total possible outcomes find distance distance = rate x timetime = distance/ rateetc average sum/ number of terms average common sense way average is 90 numbers: 89, 88, 93, 92 90 -1, -2, +3, +2 = +2need to get 88 to get average (subtract the number extra or add number needed) percent increase or decrease number increase or decrease/ original whole interest problems PRTIPrincipal x Rate x Time = Interest principal:amount money begin with rate: interest rate you're earning on the money, expressed as a decimaltime: amt of time (years) money left in accountinterest: amt of interest earn on the investment work time put in/ capacity, time to do the whole job Authorchellen12 ID51723 Card SetGRE Descriptionmath equations Updated2010-11-26T05:35:30Z Show Answers