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# Recent problems solved by 'rfer'

rfer answered: 12727 problems
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 Percentage-and-ratio-word-problems/411837: The enrollment at a gollege fell from 9600 to 9200. What is the percent of decrease?1 solutions Answer 289405 by rfer(12731)   on 2011-02-21 00:19:48 (Show Source): You can put this solution on YOUR website!400/9600=0.042=4.2%
 Linear_Equations_And_Systems_Word_Problems/411870: One angle in a triagle is 10 degrees more than the smallest angle in the triangle, while the other angle is 20 degrees more than the smallest angle. Find the measures of the three angles.1 solutions Answer 289402 by rfer(12731)   on 2011-02-21 00:15:51 (Show Source): You can put this solution on YOUR website!x+x+10+x+20=180 3x=150 x=50 x+10=60 x+20=70
 Angles/411864: an angle is 12 degrees more than 3 times its supplementary angle. find the measures of the two angles.1 solutions Answer 289400 by rfer(12731)   on 2011-02-21 00:13:49 (Show Source): You can put this solution on YOUR website!x+3x+12=180 4x=168 x=42 3x+12=138
 Inequalities/411868: Find last year's salary if this salary is 33,009.90 after a 5% raise. 1 solutions Answer 289398 by rfer(12731)   on 2011-02-21 00:11:50 (Show Source): You can put this solution on YOUR website!33009.90/1.05=31,438.00
 Miscellaneous_Word_Problems/411869: The selling price of a tv is \$675.40. If the markup is 10% of the dealers cost, what is the dealers cost of the tv?1 solutions Answer 289397 by rfer(12731)   on 2011-02-21 00:09:33 (Show Source): You can put this solution on YOUR website!675.40/1.10=614.00
 Equations/411739: 6x-7(x+9)1 solutions Answer 289362 by rfer(12731)   on 2011-02-20 20:08:27 (Show Source): You can put this solution on YOUR website!-x+63
 Numeric_Fractions/411794: what is 26 1/6 minus 6 13/161 solutions Answer 289361 by rfer(12731)   on 2011-02-20 20:06:58 (Show Source): You can put this solution on YOUR website!26 1/6 - 6 13/16 26 8/48 - 6 39/48 25 56/48 - 6 39/48 = 19 17/48
 Exponential-and-logarithmic-functions/411752: Please help me factor v^6-7291 solutions Answer 289359 by rfer(12731)   on 2011-02-20 20:02:01 (Show Source): You can put this solution on YOUR website!(v^3-27)(v^3+27)
 Graphs/411790: se the coordinates (1997,1.26) and (2006,2.31) to find the slope between the two points. 1 solutions Answer 289357 by rfer(12731)   on 2011-02-20 19:59:36 (Show Source): You can put this solution on YOUR website!m=(2.31-1.26)/(2006-1997) m=1.05/9
 percentage/411731: What is 18% of 45 ???1 solutions Answer 289356 by rfer(12731)   on 2011-02-20 19:57:04 (Show Source): You can put this solution on YOUR website!45*0.18=8.1 remember "of" means to multiply
 Quadratic_Equations/411759: Find b^2-4ac and the number of real solutions to this equation. 5x^2-7=01 solutions Answer 289345 by rfer(12731)   on 2011-02-20 19:04:36 (Show Source): You can put this solution on YOUR website!b^2-4ac a=5, b=0, c=-7 -4*5*-7=140 sqrt 140=11.83 two real solutions (-1.18,0), (1.18,0)
 Percentage-and-ratio-word-problems/411771: I still dont understand how to do percents what do i do?1 solutions Answer 289343 by rfer(12731)   on 2011-02-20 18:54:54 (Show Source): You can put this solution on YOUR website!post a problem we can walk you through.
 Quadratic_Equations/411720: Please help solve: 4x^2+2x = 0 and this one: 6x^2 = 36x Thank you1 solutions Answer 289332 by rfer(12731)   on 2011-02-20 15:58:59 (Show Source): You can put this solution on YOUR website!4x^2+2x-0 a=4, b=2, c=0 Can you go from there?
 Polynomials-and-rational-expressions/411722: Please give me the solution and its answer: 1. 3x+2>7(5x-8-6) 2. 3x+1.4-x<35 Thank You.1 solutions Answer 289331 by rfer(12731)   on 2011-02-20 15:57:28 (Show Source): You can put this solution on YOUR website!3x+2 > 35x-98 100 > 33x x < 3.03
 Linear-equations/411686: Use Intercepts graph equation 2x - 6 = 3y Are the intercepts (0, -2) Is this the only one. Can I plot (6,2) as another point?1 solutions Answer 289330 by rfer(12731)   on 2011-02-20 15:54:44 (Show Source): You can put this solution on YOUR website!put into slope intercept form first. y=mx+b 3y=2x-6 y=2/3x-2 y int b=-2 (0,-2) slope m=2/3 ------------- y=mx+b 0=2/3x-2 2/3x=2 x=3*3/2 x=6/2 x=3 x int =(3,0)
 Linear-equations/411714: Graph equation and identify y intercept y = 1/3x + y1 solutions Answer 289326 by rfer(12731)   on 2011-02-20 15:48:01 (Show Source): You can put this solution on YOUR website!y=0
 Quadratic_Equations/411687: 1. Identify the vertex of each parabolas, and idenitify if it is a maximum or minimum. a. f(x)= x^2 - 2x + 6 b. f(x) = 4(x-3)^2-11 solutions Answer 289325 by rfer(12731)   on 2011-02-20 15:46:51 (Show Source): You can put this solution on YOUR website!a) minimum vertex = (1,5) b) minimum Vertex = (3,0) If the x^2 part is positive, it opens up, so the vertex is at the minimum. If the -x^2 part is negative, it opens down, so the vertex is at the maximum. These are both positive, so they open up.
 Coordinate-system/411657: where is 5/4 on a grid1 solutions Answer 289322 by rfer(12731)   on 2011-02-20 15:36:38 (Show Source): You can put this solution on YOUR website!Is this a y value , an X value or the slope?
 Money_Word_Problems/411696: what is the interest of 4,300 for a 12 months at 4.6%1 solutions Answer 289321 by rfer(12731)   on 2011-02-20 15:34:14 (Show Source): You can put this solution on YOUR website!I=P*r I=4300*0.046 I=198.80
 Functions/411709: y=0.15x+0.79 what is the y-intercept? 1 solutions Answer 289320 by rfer(12731)   on 2011-02-20 15:32:26 (Show Source): You can put this solution on YOUR website!y int = 0.79
 Numeric_Fractions/411694: (-2/3-7/3)(1/3-9/10) I need help by seeing how this is worked out1 solutions Answer 289319 by rfer(12731)   on 2011-02-20 15:31:23 (Show Source): You can put this solution on YOUR website!first, find common denominator (-2/3-7/3)(10/30-27/30) (-9/3)(-17/30)=153/90=1 7/10
 Parallelograms/411698: 6x-8=4x-21 solutions Answer 289317 by rfer(12731)   on 2011-02-20 15:26:59 (Show Source): You can put this solution on YOUR website!2x=6 x=3
 Linear-equations/411467: I am having trouble solving this problem for "slope intercept form" 5y=6x I know the form is y =mx+b but can't get this one figured out?1 solutions Answer 289226 by rfer(12731)   on 2011-02-19 20:44:29 (Show Source): You can put this solution on YOUR website!y=6/5x the y int =(0,0)
 Travel_Word_Problems/411410: Airspeed of a Plane Two ground observers are 20 mi apart. They communicate with each other by cell phone and note that a passenger plane has passed over each of them exactly 5 minutes apart. If this plane is flying into a 50-mi/h headwind, what is the airspeed of this plane? What I tried: Distance=Rate x Time 50-20= r x 12 Since time must be in hour i converted 5 minutes by dividing by 60 1 solutions Answer 289220 by rfer(12731)   on 2011-02-19 20:32:55 (Show Source): You can put this solution on YOUR website!50-20=0.083x 30/0.083=x x=375 mph
 Graphs/411463: 8x-(6x+8)=6 solve1 solutions Answer 289219 by rfer(12731)   on 2011-02-19 20:26:25 (Show Source): You can put this solution on YOUR website!8x-6x=6+8 2x=14 x=7
 Volume/411416: How do I find the height of a cone with an approximate volume of 134 cm3 and a radius of 4 cm?1 solutions Answer 289218 by rfer(12731)   on 2011-02-19 20:25:13 (Show Source): You can put this solution on YOUR website!V=pir^2h/3 134=3.14*16*h/3 134*3=50.24h h=134/50.24 h=2.67 cm
 Equations/411415: 5/9X+1/3=61 solutions Answer 289217 by rfer(12731)   on 2011-02-19 20:21:04 (Show Source): You can put this solution on YOUR website!5/9x=6-1/3 5/9x=5 2/3 x=17/3*9/5 x=153/15 x=10 1/5
 Geometry_Word_Problems/411460: ``how many linear feet of fencing would be needed to enclose a rectangular garden that measures 30 feet long by 8feet wide. explain how you got your answer.''1 solutions Answer 289215 by rfer(12731)   on 2011-02-19 20:17:51 (Show Source): You can put this solution on YOUR website!P=2W+2L P=2*8+2*30 p=76 ft
 Linear-equations/411402: Solve for x -1 = -1/2x - 41 solutions Answer 289214 by rfer(12731)   on 2011-02-19 20:16:05 (Show Source): You can put this solution on YOUR website!3=-1/2x 3*-2/1=x x=-6
 Graphs/411452: Find the slope if it exists, of the line containing the pair of points. (-5.1,2.8) and (-4.9,2.6) the slope is?1 solutions Answer 289212 by rfer(12731)   on 2011-02-19 20:13:10 (Show Source): You can put this solution on YOUR website!slope m=(2.6-2.8)/(-4.9--5.1) m=-.2/.2 m=-1
 Functions/411454: Given the function K(s)=2s+9, find each of the following. K(4)= K (-7)= K (6.6)=1 solutions Answer 289211 by rfer(12731)   on 2011-02-19 20:10:03 (Show Source): You can put this solution on YOUR website!k(4)=2*4+9 k(4)=8+9 k(4)=17