# See tutors' answers!

Algebra ->  Tutoring on algebra.com -> See tutors' answers!      Log On

 Tutoring Home For Students Tools for Tutors Our Tutors Register Recently Solved
 By Tutor
| By Problem Number |

Tutor:

# Recent problems solved by 'rfer'

rfer answered: 12725 problems
Jump to solutions: 0..29 , 30..59 , 60..89 , 90..119 , 120..149 , 150..179 , 180..209 , 210..239 , 240..269 , 270..299 , 300..329 , 330..359 , 360..389 , 390..419 , 420..449 , 450..479 , 480..509 , 510..539 , 540..569 , 570..599 , 600..629 , 630..659 , 660..689 , 690..719 , 720..749 , 750..779 , 780..809 , 810..839 , 840..869 , 870..899 , 900..929 , 930..959 , 960..989 , 990..1019 , 1020..1049 , 1050..1079 , 1080..1109 , 1110..1139 , 1140..1169 , 1170..1199 , 1200..1229 , 1230..1259 , 1260..1289 , 1290..1319 , 1320..1349 , 1350..1379 , 1380..1409 , 1410..1439 , 1440..1469 , 1470..1499 , 1500..1529 , 1530..1559 , 1560..1589 , 1590..1619 , 1620..1649 , 1650..1679 , 1680..1709 , 1710..1739 , 1740..1769 , 1770..1799 , 1800..1829 , 1830..1859 , 1860..1889 , 1890..1919 , 1920..1949 , 1950..1979 , 1980..2009 , 2010..2039 , 2040..2069 , 2070..2099 , 2100..2129 , 2130..2159 , 2160..2189 , 2190..2219 , 2220..2249 , 2250..2279 , 2280..2309 , 2310..2339 , 2340..2369 , 2370..2399 , 2400..2429 , 2430..2459 , 2460..2489 , 2490..2519 , 2520..2549 , 2550..2579 , 2580..2609 , 2610..2639 , 2640..2669 , 2670..2699 , 2700..2729 , 2730..2759 , 2760..2789 , 2790..2819 , 2820..2849 , 2850..2879 , 2880..2909 , 2910..2939 , 2940..2969 , 2970..2999 , 3000..3029 , 3030..3059 , 3060..3089 , 3090..3119 , 3120..3149 , 3150..3179 , 3180..3209 , 3210..3239 , 3240..3269 , 3270..3299 , 3300..3329 , 3330..3359 , 3360..3389 , 3390..3419 , 3420..3449 , 3450..3479 , 3480..3509 , 3510..3539 , 3540..3569 , 3570..3599 , 3600..3629 , 3630..3659 , 3660..3689 , 3690..3719 , 3720..3749 , 3750..3779 , 3780..3809 , 3810..3839 , 3840..3869 , 3870..3899 , 3900..3929 , 3930..3959 , 3960..3989 , 3990..4019 , 4020..4049 , 4050..4079 , 4080..4109 , 4110..4139 , 4140..4169 , 4170..4199 , 4200..4229 , 4230..4259 , 4260..4289 , 4290..4319 , 4320..4349 , 4350..4379 , 4380..4409 , 4410..4439 , 4440..4469 , 4470..4499 , 4500..4529 , 4530..4559 , 4560..4589 , 4590..4619 , 4620..4649 , 4650..4679 , 4680..4709 , 4710..4739 , 4740..4769 , 4770..4799 , 4800..4829 , 4830..4859 , 4860..4889 , 4890..4919 , 4920..4949 , 4950..4979 , 4980..5009 , 5010..5039 , 5040..5069 , 5070..5099 , 5100..5129 , 5130..5159 , 5160..5189 , 5190..5219 , 5220..5249 , 5250..5279 , 5280..5309 , 5310..5339 , 5340..5369 , 5370..5399 , 5400..5429 , 5430..5459 , 5460..5489 , 5490..5519 , 5520..5549 , 5550..5579 , 5580..5609 , 5610..5639 , 5640..5669 , 5670..5699 , 5700..5729 , 5730..5759 , 5760..5789 , 5790..5819 , 5820..5849 , 5850..5879 , 5880..5909 , 5910..5939 , 5940..5969 , 5970..5999 , 6000..6029 , 6030..6059 , 6060..6089 , 6090..6119 , 6120..6149 , 6150..6179 , 6180..6209 , 6210..6239 , 6240..6269 , 6270..6299 , 6300..6329 , 6330..6359 , 6360..6389 , 6390..6419 , 6420..6449 , 6450..6479 , 6480..6509 , 6510..6539 , 6540..6569 , 6570..6599 , 6600..6629 , 6630..6659 , 6660..6689 , 6690..6719 , 6720..6749 , 6750..6779 , 6780..6809 , 6810..6839 , 6840..6869 , 6870..6899 , 6900..6929 , 6930..6959 , 6960..6989 , 6990..7019 , 7020..7049 , 7050..7079 , 7080..7109 , 7110..7139 , 7140..7169 , 7170..7199 , 7200..7229 , 7230..7259 , 7260..7289 , 7290..7319 , 7320..7349 , 7350..7379 , 7380..7409 , 7410..7439 , 7440..7469 , 7470..7499 , 7500..7529 , 7530..7559 , 7560..7589 , 7590..7619 , 7620..7649 , 7650..7679 , 7680..7709 , 7710..7739 , 7740..7769 , 7770..7799 , 7800..7829 , 7830..7859 , 7860..7889 , 7890..7919 , 7920..7949 , 7950..7979 , 7980..8009 , 8010..8039 , 8040..8069 , 8070..8099 , 8100..8129 , 8130..8159 , 8160..8189 , 8190..8219 , 8220..8249 , 8250..8279 , 8280..8309 , 8310..8339 , 8340..8369 , 8370..8399 , 8400..8429 , 8430..8459 , 8460..8489 , 8490..8519 , 8520..8549 , 8550..8579 , 8580..8609 , 8610..8639 , 8640..8669 , 8670..8699 , 8700..8729 , 8730..8759 , 8760..8789 , 8790..8819 , 8820..8849 , 8850..8879 , 8880..8909 , 8910..8939 , 8940..8969 , 8970..8999 , 9000..9029 , 9030..9059 , 9060..9089 , 9090..9119 , 9120..9149 , 9150..9179 , 9180..9209 , 9210..9239 , 9240..9269 , 9270..9299 , 9300..9329 , 9330..9359 , 9360..9389 , 9390..9419 , 9420..9449 , 9450..9479 , 9480..9509 , 9510..9539 , 9540..9569 , 9570..9599 , 9600..9629 , 9630..9659 , 9660..9689 , 9690..9719 , 9720..9749 , 9750..9779 , 9780..9809 , 9810..9839 , 9840..9869 , 9870..9899 , 9900..9929 , 9930..9959 , 9960..9989 , 9990..10019 , 10020..10049 , 10050..10079 , 10080..10109 , 10110..10139 , 10140..10169 , 10170..10199 , 10200..10229 , 10230..10259 , 10260..10289 , 10290..10319 , 10320..10349 , 10350..10379 , 10380..10409 , 10410..10439 , 10440..10469 , 10470..10499 , 10500..10529 , 10530..10559 , 10560..10589 , 10590..10619 , 10620..10649 , 10650..10679 , 10680..10709 , 10710..10739 , 10740..10769 , 10770..10799 , 10800..10829 , 10830..10859 , 10860..10889 , 10890..10919 , 10920..10949 , 10950..10979 , 10980..11009 , 11010..11039 , 11040..11069 , 11070..11099 , 11100..11129 , 11130..11159 , 11160..11189 , 11190..11219 , 11220..11249 , 11250..11279 , 11280..11309 , 11310..11339 , 11340..11369 , 11370..11399 , 11400..11429 , 11430..11459 , 11460..11489 , 11490..11519 , 11520..11549 , 11550..11579 , 11580..11609 , 11610..11639 , 11640..11669 , 11670..11699 , 11700..11729 , 11730..11759 , 11760..11789 , 11790..11819 , 11820..11849 , 11850..11879 , 11880..11909 , 11910..11939 , 11940..11969 , 11970..11999 , 12000..12029 , 12030..12059 , 12060..12089 , 12090..12119 , 12120..12149 , 12150..12179 , 12180..12209 , 12210..12239 , 12240..12269 , 12270..12299 , 12300..12329 , 12330..12359 , 12360..12389 , 12390..12419 , 12420..12449 , 12450..12479 , 12480..12509 , 12510..12539 , 12540..12569 , 12570..12599 , 12600..12629 , 12630..12659 , 12660..12689 , 12690..12719 , 12720..12749, >>Next

 test/708350: (2x - 3) (2x + 3) Write the products1 solutions Answer 436081 by rfer(12729)   on 2013-01-30 15:22:45 (Show Source): You can put this solution on YOUR website!4x^2+6x-6x-9 =4x^2-9
 Finance/708353: Please help me sole this equation in simple interest I=\$30, r=4%, t=2 years1 solutions Answer 436080 by rfer(12729)   on 2013-01-30 15:21:04 (Show Source): You can put this solution on YOUR website!I=Prt 30=P*0.04*2 30/0.08=P \$375=P
 Distributive-associative-commutative-properties/708357: How do you solve 2x-(8x-1)-151 solutions Answer 436079 by rfer(12729)   on 2013-01-30 15:18:59 (Show Source): You can put this solution on YOUR website!2x-8x+1-15=-6x-14
 Percentage-and-ratio-word-problems/708354: Stan spent 65% of his money and had 266 left How much had he left at first?1 solutions Answer 436078 by rfer(12729)   on 2013-01-30 15:17:58 (Show Source): You can put this solution on YOUR website!266/0.35=\$760
 Numeric_Fractions/708276: if 8x8=13x5 then prove it1 solutions Answer 436037 by rfer(12729)   on 2013-01-30 11:57:05 (Show Source): You can put this solution on YOUR website!64=65 won't prove
 Numeric_Fractions/708282: 7/2 divided by 12/3 = 1 solutions Answer 436034 by rfer(12729)   on 2013-01-30 11:55:33 (Show Source): You can put this solution on YOUR website!7/2*3/12=21/24=7/8
 Numbers_Word_Problems/708277: Five less than the product of two and a number is six more than that number. Find the number.1 solutions Answer 436033 by rfer(12729)   on 2013-01-30 11:54:33 (Show Source): You can put this solution on YOUR website!2x-5=x+6 x=11
 Quadratic_Equations/708082: How do I solve for x in this equation: y=0.5x^3 when y=71 solutions Answer 435980 by rfer(12729)   on 2013-01-29 23:14:53 (Show Source): You can put this solution on YOUR website!7/0.5=x^3 14=x^3 curt 14=x x=2.41
 Inequalities/708100: what is the answer to the inequality 5-6(x-4)<-(6-x) 1 solutions Answer 435979 by rfer(12729)   on 2013-01-29 23:09:57 (Show Source): You can put this solution on YOUR website!5-6x+24 < -6+x -7x < -6-29 -7x < -35 x < -35/-7 x < 5
 Linear-equations/708130: Fine the slope of the line that passes through the pair of points? (2,-2) (-3,-4)1 solutions Answer 435978 by rfer(12729)   on 2013-01-29 23:03:38 (Show Source): You can put this solution on YOUR website!slope m=(-4--2)/(-3-2) m=-2/-5 m=2/5
 Human-and-algebraic-language/707967: Five less than a product of a number and two is twenty one1 solutions Answer 435934 by rfer(12729)   on 2013-01-29 19:37:10 (Show Source): You can put this solution on YOUR website!2x-5=21 2x=26 x=26/2 x=13
 test/707964: -24/(-5/12)1 solutions Answer 435932 by rfer(12729)   on 2013-01-29 19:36:16 (Show Source): You can put this solution on YOUR website!-24*-12/5=+57.6=+57 3/5
 Angles/707423: One of two supplementary angles is 8 degrees larger than the other. Find the measure of the larger angle.1 solutions Answer 435695 by rfer(12729)   on 2013-01-28 19:58:24 (Show Source): You can put this solution on YOUR website!x+x+8=180 2x=180-8 2x=172 x=172/2 x=86 x+8=94
 Travel_Word_Problems/707426: A bus leaves Los Angeles traveling at 50 mi/hr. An hour later a car traveling on the same road leaves at 70 mi/hr to try and overtake the bus. How far from Los Angeles does the car overtake the bus?1 solutions Answer 435694 by rfer(12729)   on 2013-01-28 19:56:52 (Show Source): You can put this solution on YOUR website!50 mi lead 20 mph overtake 50/20=2.5 hrs 2.5*50+50=175 miles
 test/707039: Find an equation of a line that passes through the points (-1,2) and (5,0) Thank you1 solutions Answer 435487 by rfer(12729)   on 2013-01-28 01:46:59 (Show Source): You can put this solution on YOUR website!slope m=(0-2)/(5--1) m=-2/6 m=-1/3 ---------------- y=mx+b 2=-1/3*-1+b 2=1/3+b b=5/3 ------------ y=-1/3x+5/3
 Expressions-with-variables/707002: solve 2+2[b-5(b-3)]1 solutions Answer 435486 by rfer(12729)   on 2013-01-28 01:42:42 (Show Source): You can put this solution on YOUR website!2+2[b-5(b-3)] 2+2[b-5b+15} 2+8b+30 =8b+32
 Equations/707020: Please help me solve this equation 4/7x = -121 solutions Answer 435485 by rfer(12729)   on 2013-01-28 01:38:14 (Show Source): You can put this solution on YOUR website!x=-12/(4/7) x=-12*7/4 x=-21
 Expressions-with-variables/707040: How do we do this problem y=-2x+12 3y+x=111 solutions Answer 435484 by rfer(12729)   on 2013-01-28 01:35:57 (Show Source): You can put this solution on YOUR website!y=-2x+12 ----------- 3y+x=11 3(-2x+12)+x=11 -6x+36+x=11 -5x=11-36 -5x=-25 x=-25/-5 x=5 -------------- 3y+5=11 3y=11-5 3y=6 y=6/3 y=2 --------------- (5,2) ----------- 2=-2*5+12 2=-10+12 2=2
 test/706922: Solve I=PRT for P1 solutions Answer 435452 by rfer(12729)   on 2013-01-27 20:48:32 (Show Source): You can put this solution on YOUR website!P=I/rt
 Money_Word_Problems/706931: \$1500.00 divided by 2%=1 solutions Answer 435450 by rfer(12729)   on 2013-01-27 20:46:36 (Show Source): You can put this solution on YOUR website!2500/0.02=\$75,000
 Numeric_Fractions/706972: y + 3/4 =9 1/21 solutions Answer 435448 by rfer(12729)   on 2013-01-27 20:44:53 (Show Source): You can put this solution on YOUR website!y=38/4-3/4 y=35/4=8 3/4
 Money_Word_Problems/706975: If a business gains 8% in one year and loses 3% the following year, what is the percentage gain over two years?1 solutions Answer 435445 by rfer(12729)   on 2013-01-27 20:43:18 (Show Source): You can put this solution on YOUR website!1000*1.08=1080/1.03=1048.54 48.54/1000=0.04854=4.854% I like to use fictitous figures for these kind of problems. It makes it easier to see what is happening.
 Mixture_Word_Problems/706815: On a world globe, the distance between Rio de Janerio and Hong Kong, two cities that are actually 17615 kilometers apart, is 21.5 inches. The actual distance between Paris and Stockholm is 1605 kilometers. How far apart are Paris and Stockholm on the same world globe?1 solutions Answer 435415 by rfer(12729)   on 2013-01-27 17:03:21 (Show Source): You can put this solution on YOUR website!17615/21.5=1605/x 17615x=34507.5 x=34507.5/17615 x=1.96 in
 test/706823: 4/5=2x/25 this is a proportion 1 solutions Answer 435413 by rfer(12729)   on 2013-01-27 16:59:54 (Show Source): You can put this solution on YOUR website!10x=100 x=100/10 x=10
 Linear-equations/706827: ∛-125 how to work this problem please!1 solutions Answer 435412 by rfer(12729)   on 2013-01-27 16:57:48 (Show Source): You can put this solution on YOUR website!=-5
 Numbers_Word_Problems/706867: One positive number is 1/5 of another number. The difference between the two numbers is 76. Find the numbers.1 solutions Answer 435410 by rfer(12729)   on 2013-01-27 16:52:11 (Show Source): You can put this solution on YOUR website!x-1/5x=76 4/5x=76 x=76/(4/5) x=76*5/4 x=95 ----- 95-1/5*95=76 95-19=76
 Linear_Equations_And_Systems_Word_Problems/706869: If 9 is added to twice a number and the sum is multiplied by 3 the result is the same as if the number is multiplied by 4 and 11 is added to the product what is the number1 solutions Answer 435408 by rfer(12729)   on 2013-01-27 16:48:25 (Show Source): You can put this solution on YOUR website!3(2x+9)=4x+11 6x+27=4x+11 2x=11-27 2x=-16 x=-16/2 x=-8 ------------- 3(2*-8+9)=4*-8+11 3*-7=-32+11 -21=-21
 test/706583: The sum of two numbers is -18. Two times the first number minus three times the second number is 59. What are the numbers?1 solutions Answer 435282 by rfer(12729)   on 2013-01-26 20:31:51 (Show Source): You can put this solution on YOUR website!x+y=-18 y=-x-18 ------- 2x-3y=59 2x-3(-x-18)=59 2x+3x+54=59 5x=5 x=1 ------------- 2*1-3y=59 -3y=59-2 y=57/-3 y=-19 ---------------
 Equations/706597: A woman earns 10% more than her husband. Together they make \$72,240 per year. What is the husband's annual salary?1 solutions Answer 435280 by rfer(12729)   on 2013-01-26 20:26:29 (Show Source): You can put this solution on YOUR website!x+1.10x=72240 2.10x=72240 x=72240/2.10 x=\$34,400 His 1.10x=\$37,840 Hers
 Equations/706601: What annual rate of interest would you have to earn on an investment of \$5500 to ensure receiving \$368.50 interest after 1 year?1 solutions Answer 435279 by rfer(12729)   on 2013-01-26 20:22:52 (Show Source): You can put this solution on YOUR website!I=Prt 368.50=5500r*1 368.50/5500=r 0.067=6.7%
 Equations/706603: An executive in an engineering firm earns a monthly salary plus a Christmas bonus of \$530. If she earns a total of \$68,930 per year, what is her monthly salary?1 solutions Answer 435278 by rfer(12729)   on 2013-01-26 20:20:08 (Show Source): You can put this solution on YOUR website!(68930-530)/12=\$5700