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Recent problems solved by 'rfer'

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Length-and-distance/620602: Write the equation of a line this is parallel to y=-4x+5 and passes through point (-6,21). 1 solutions Answer 390284 by rfer(12644)   on 2012-06-13 17:10:20 (Show Source): You can put this solution on YOUR website! 21=-4*-6+b 21=24+b 21-24=b b=-3 --------------------- y=-4x-3

Rectangles/620601: The width of a rectangle is 35cm and the area is 1400cm. Find the perimeter? 1 solutions Answer 390283 by rfer(12644)   on 2012-06-13 17:08:33 (Show Source): You can put this solution on YOUR website! 1400/35=40 P=2*35+2*40 P=150 cm

Polynomials-and-rational-expressions/620571: Divide x^2+6x-31/x+9 1 solutions Answer 390277 by rfer(12644)   on 2012-06-13 17:04:01 (Show Source): You can put this solution on YOUR website! =x-3 R=-4

Travel_Word_Problems/620599: Minh walked a total of 4 miles in 75 minutes. It he walked at 3.5 miles per hour for the first 30 minutes, what was his average speed for the rest of the time? 1 solutions Answer 390276 by rfer(12644)   on 2012-06-13 16:59:54 (Show Source): You can put this solution on YOUR website! 3.5/2=1.75 4-1.75=2.25 2.25/(35/60)=3.9 mph

Complex_Numbers/620586: Perform the indicated operation, simplify, and express in standard form. 6(9-8i)= 1 solutions Answer 390272 by rfer(12644)   on 2012-06-13 16:56:40 (Show Source): You can put this solution on YOUR website! =54-48i =-48i+54

test/620595: 9+x=9 1 solutions Answer 390271 by rfer(12644)   on 2012-06-13 16:51:29 (Show Source): You can put this solution on YOUR website! x=9-9 x=0

Linear-equations/620591: Find the slope of the altitude to the line passing through (5,2) and (9,-6) 1 solutions Answer 390270 by rfer(12644)   on 2012-06-13 16:50:58 (Show Source): You can put this solution on YOUR website! m=(-6-2)/(9-5) m=-8/4 m=-2

Linear-systems/620593: graph the solution of y-2>1 on a number line (linear inequalities) i know how to graph it what i don't know is how to calculate y-2>1 1 solutions Answer 390268 by rfer(12644)   on 2012-06-13 16:49:25 (Show Source): You can put this solution on YOUR website! y-2 > 1 y > 2+1 y > 3 circle around +3 with arrow to the right

Geometry_Word_Problems/619561: the perimeter of a standard-size regular rug is 36ft. the length is 2 feet longer than the width. find the dimension. 1 solutions Answer 389695 by rfer(12644)   on 2012-06-10 20:59:15 (Show Source): You can put this solution on YOUR website! 2x+2(x+2)=36 2x+2x+4=36 4x=36-4 4x=32 x=32/4 x=8ft x+2=10ft

percentage/619498: what % increase is 3744 from 3383 1 solutions Answer 389687 by rfer(12644)   on 2012-06-10 19:29:06 (Show Source): You can put this solution on YOUR website! 3744-3383=361 361/3383=0.107=10.7%

Expressions-with-variables/618864: subtracting sums 35-(3a+14) 1 solutions Answer 389179 by rfer(12644)   on 2012-06-07 22:14:25 (Show Source): You can put this solution on YOUR website! 35-3a-14=21-3a

Equations/618880: What is the answer to x/9=5/6? 1 solutions Answer 389177 by rfer(12644)   on 2012-06-07 22:12:19 (Show Source): You can put this solution on YOUR website! x=5/6*9/1 x=45/6 x=7.5 x=7 1/2

Travel_Word_Problems/618914: An automobile traveled 1805 miles in 38 hours. What was the average rate of travel per hour? 1 solutions Answer 389176 by rfer(12644)   on 2012-06-07 22:09:26 (Show Source): You can put this solution on YOUR website! 1805/38=47.5 mph

Complex_Numbers/618814: (8 - 3i) - (17 - 7i) 1 solutions Answer 389151 by rfer(12644)   on 2012-06-07 17:56:39 (Show Source): You can put this solution on YOUR website! 8-3i-17+7i= -9+4i

Numeric_Fractions/618792: Cut a piece of wood measuring 5 1/8 inches into two equal pieces. How long is each piece. 1 solutions Answer 389150 by rfer(12644)   on 2012-06-07 17:55:05 (Show Source): You can put this solution on YOUR website! 5 1/8=5.125 5.125/2=2.2625 2.2625=2 21/80

Exponents-negative-and-fractional/618816: -18/35 divided 22/25 1 solutions Answer 389148 by rfer(12644)   on 2012-06-07 17:51:53 (Show Source): You can put this solution on YOUR website! -18/35*25/22=-450/770=-45/77

Travel_Word_Problems/618839: Rene is going to the lake to visit some friends. If the lake is 60 miles away, and Rene is driving at 40 miles per hour the entire time, how long will it take her to get to the lake? 1 solutions Answer 389147 by rfer(12644)   on 2012-06-07 17:49:02 (Show Source): You can put this solution on YOUR website! 60/40=1.5 hrs

Average/616666: if i got 18 wrong on a test i took and there are 50 questions. whats my score in percentage ? like do i get a 64% ?? because i divided and then multiplied .. i dont know ... can you help me please. 1 solutions Answer 387830 by rfer(12644)   on 2012-05-31 16:23:48 (Show Source): You can put this solution on YOUR website! 50-18=32 32/50=0.64=64% Try to use proper English.

expressions/616386: 1/11 + 5/6 1 solutions Answer 387677 by rfer(12644)   on 2012-05-30 21:20:38 (Show Source): You can put this solution on YOUR website! 6/66+55/66=61/66

Money_Word_Problems/616320: Darcy earns a salary of $1400 per month, plus a commission of 4% of her sales. She wants to earn a total of at least $1600 this month. What is the least amount of sales she needs? 1 solutions Answer 387633 by rfer(12644)   on 2012-05-30 17:12:42 (Show Source): You can put this solution on YOUR website! 200/0.04=$5000

Polygons/615971: Solve for x. 83+60+x+(x/3-11)=360 Please answer!! 1 solutions Answer 387454 by rfer(12644)   on 2012-05-29 21:07:45 (Show Source): You can put this solution on YOUR website! 143+2x/3-11=360 2x/3=228 2x=228*3 2x=684 x=684/2 x=342

Numbers_Word_Problems/616000: the second of two numbers is 7 times the first. their sum is 72. find the numbers. what are the numbers? 1 solutions Answer 387452 by rfer(12644)   on 2012-05-29 21:02:14 (Show Source): You can put this solution on YOUR website! x+7x=72 8x=72 x=72/8 x=9 7x=63

Angles/615608: Twenty more than five times the measure of an angle is 60 degrees. What is the measure of the angle? 1 solutions Answer 387263 by rfer(12644)   on 2012-05-28 23:39:44 (Show Source): You can put this solution on YOUR website! 5x+20=60 5x=60-20 5x=40 x=40/5 x=8

Trigonometry-basics/615621: which expression is equivalent to sin (-120) 1 solutions Answer 387262 by rfer(12644)   on 2012-05-28 23:37:35 (Show Source): You can put this solution on YOUR website! -0.866

Graphs/615657: What is the length of the missing side of the triangle? If necessary, round to the nearest tenth. One side of the triangle has the length of 19 and second side has 14. Answer choices: a) 16.5 b) 33 c) 12.8 d) 23.6 1 solutions Answer 387261 by rfer(12644)   on 2012-05-28 23:34:57 (Show Source): You can put this solution on YOUR website! c 12.8

real-numbers/615610: What is the answer to this problem? 5/7 divided by (-5/6)(-6/7/) 1 solutions Answer 387250 by rfer(12644)   on 2012-05-28 21:08:23 (Show Source): You can put this solution on YOUR website! =36/49

Travel_Word_Problems/615549: what is the average speed of a train if it takes 16 hours to travel 1200 miles 1 solutions Answer 387231 by rfer(12644)   on 2012-05-28 18:40:01 (Show Source): You can put this solution on YOUR website! 1200/16=75 mph

Mixture_Word_Problems/615566: donna redeems a 10% off coupon at her local nursery. after buying azaleas, bougainvillea, and bags of potting soil, her checkout price before tax was $217.95. how much would she have paid without the coupon? 1 solutions Answer 387228 by rfer(12644)   on 2012-05-28 18:38:38 (Show Source): You can put this solution on YOUR website! 217.95/0.90=$242.17

test/615429: Hello, I would like some help with this question: The lenght of a rectangular garden is 5 feet longer than twice its width.If the perimeter of th garden is 130 feet, ind its dimensions. Thanks 1 solutions Answer 387172 by rfer(12644)   on 2012-05-28 11:54:13 (Show Source): You can put this solution on YOUR website! 2x+2(2x+5)=130 2x+4x+10=130 6x=120 x=120/6 x=20 2x+5=45

percentage/615431: what is 5.9% of 14400? 1 solutions Answer 387171 by rfer(12644)   on 2012-05-28 11:52:08 (Show Source): You can put this solution on YOUR website! 14400*0.059=8496

Numeric_Fractions/615326: 1/6 + (-9/11) 1 solutions Answer 387067 by rfer(12644)   on 2012-05-27 20:33:46 (Show Source): You can put this solution on YOUR website! 1/6-9/11 11/66-54/66=-43/66