See tutors' answers!

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


   
By Tutor
 | By Problem Number | 

Tutor:
New! Get regular updates about newly solved problems via algebra.com's RSS system.

Recent problems solved by 'rfer'

rfer answered: 12656 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, >>Next

Angles/460392: Find the supplement of the complement of a 51 degree angle.
1 solutions

Answer 315770 by rfer(12660) About Me  on 2011-06-12 21:19:26 (Show Source):
You can put this solution on YOUR website!
90-51=39
180-39=141 degrees


Travel_Word_Problems/460338: Two trains leave stations 336 miles apart at the same time and travel toward each other. One train travels at 75 miles per hour while the other travels at 65 miles per hour. How long will it take for the two trains to meet?
1 solutions

Answer 315769 by rfer(12660) About Me  on 2011-06-12 21:16:08 (Show Source):
You can put this solution on YOUR website!
approaching at 140 mph
336/140=2.4 hrs=2 hrs 24 min


Graphs/460383: Graph the line containing the given pair of points and find the slope. (3,2), (-6,-5)
1 solutions

Answer 315766 by rfer(12660) About Me  on 2011-06-12 21:09:34 (Show Source):
You can put this solution on YOUR website!
slope
m=(-5-2)/(-6-3)
m=-7/-9
m=7/9


Travel_Word_Problems/460385: If you fly a plane going north for 4 hours and make it 400 km, what was your velocity
1 solutions

Answer 315765 by rfer(12660) About Me  on 2011-06-12 21:07:34 (Show Source):


Finance/460302: A real estate agent works on 11% commission. What is her commission on a house that she sold for $390,600?
1 solutions

Answer 315731 by rfer(12660) About Me  on 2011-06-12 18:19:40 (Show Source):
You can put this solution on YOUR website!
390600*0.11=$42,966


Money_Word_Problems/460312: If 4x - 7 = 2x + 5, what is x?
1 solutions

Answer 315730 by rfer(12660) About Me  on 2011-06-12 18:17:37 (Show Source):


Proportions/460298: Find the discount on a book that is $14.95 and on sale for 20%
1 solutions

Answer 315706 by rfer(12660) About Me  on 2011-06-12 16:56:40 (Show Source):
You can put this solution on YOUR website!
14.95/.8=18.69
18.69-14.95=$3.74


Polynomials-and-rational-expressions/460214: Essay: Show all work. Find the following product: (y-7)^2
1 solutions

Answer 315705 by rfer(12660) About Me  on 2011-06-12 16:52:31 (Show Source):
You can put this solution on YOUR website!
(y-7)(y-7)
y^2-7y-7y+49
y^2-14y+49


Proportions/460294: Find the amount of simple interest on an investment of $3,100 for 2 and a half years at an annual rate of 4 3/4%. Round to the nearest cent
1 solutions

Answer 315703 by rfer(12660) About Me  on 2011-06-12 16:48:43 (Show Source):
You can put this solution on YOUR website!
I=Prt
I=3100*0.0475*2.5
I=$368.13


Miscellaneous_Word_Problems/460292: I am having trouble with this last question can anyone help me with this. I have part a and b but I am having trouble with part c of this question. Thanks so much for the help.

3. You recently started the paperwork to purchase your new home, and you were just notified that you can move into the house in 2 weeks. You decide to hire a moving company, but are unsure which company to choose. You search online and are interested in contacting two companies, Heavy Lifters and Quick Move, to discuss their rates. Heavy Lifting charges a $75 fee plus $30 per hour. Quick Move charges $45 per hour with no additional fees.
a) Which mover provides a better deal for 12 hours of work? How did you arrive at your answer?
b) Which mover provides a better deal for 3 hours of work? How did you arrive at your answer?
c) For what values h (hours) does Heavy Lifting offer the better deal? Express your answer as an inequality. Explain how you reached your answer.

1 solutions

Answer 315702 by rfer(12660) About Me  on 2011-06-12 16:46:41 (Show Source):
You can put this solution on YOUR website!
C)
75+30x < 45x
75 < 15x
5 < x
more than 5 hrs


Money_Word_Problems/460293: Suppose you are setting up for a mall business and have invested $10,000 to produce an item that will sell for $15. If each unit can be produced for $9 how many units must you sell to break even?
1 solutions

Answer 315701 by rfer(12660) About Me  on 2011-06-12 16:43:11 (Show Source):
You can put this solution on YOUR website!
10000/6=1667 units


Inequalities/460242: (3x – 3.5) – (x + 1.8) subtracting polynomials
1 solutions

Answer 315699 by rfer(12660) About Me  on 2011-06-12 16:41:25 (Show Source):
You can put this solution on YOUR website!
3x-3.5-x-1.8=2x-5.3


Graphs/460254: find the x intercept 2x+y=7
1 solutions

Answer 315698 by rfer(12660) About Me  on 2011-06-12 16:39:41 (Show Source):
You can put this solution on YOUR website!
2x+0=7
2x=7
x=3.5
(3.5,0)


Proportions/460282: A utility pole 8 meters tall cast a 12 meter shadow. at the same time a building cast a 99 meter shadow. How tall is the building?
1 solutions

Answer 315695 by rfer(12660) About Me  on 2011-06-12 16:35:21 (Show Source):
You can put this solution on YOUR website!
8/12=x/99
12x=792
x=66 meters


Proportions/460284: Five less than a number is at least 11.
A. Write an inequality for the sentence.
B. Solve the inequality on a number line.
Explain your answer.
1 solutions

Answer 315694 by rfer(12660) About Me  on 2011-06-12 16:34:00 (Show Source):


Equations/460289: Word problem :
The total number of Democrats and Republicans in the U.S House of Representatives during the 109th session was 434. There were 30 more Republicans than Democrats . How many members of each party were there ?
1 solutions

Answer 315693 by rfer(12660) About Me  on 2011-06-12 16:32:27 (Show Source):
You can put this solution on YOUR website!
x+x+30=434
2x=404
x=202 Dems
x+30=232 Rep


Inequalities/460288: (3x2 – 10x – 8) ÷ (3x + 2) I need help dividing this polynomial
1 solutions

Answer 315692 by rfer(12660) About Me  on 2011-06-12 16:30:46 (Show Source):


Inequalities/460287: (4x2 + 3x ) + ( 4x + 5) I need help adding this polynomial
1 solutions

Answer 315691 by rfer(12660) About Me  on 2011-06-12 16:27:27 (Show Source):


Proportions/460285: -7/10 = 2 2/5d
A. -1 7/10 B. -3 1/10 C. -7/24 D. -1 17/25
1 solutions

Answer 315690 by rfer(12660) About Me  on 2011-06-12 16:26:32 (Show Source):
You can put this solution on YOUR website!
d=-7/10*5/12
d=-35/120
d=-7/24 (C)


Inequalities/460069: What is the answer to this inequality 9x + 7 < 8x -2? show all the steps to get the answer.
1 solutions

Answer 315547 by rfer(12660) About Me  on 2011-06-11 21:00:37 (Show Source):
You can put this solution on YOUR website!
9x-8x < -2-7
x < -9


Equations/460064: 3x+5/9+2x-1/9=7/9
Could you show your steps please, thanks!
1 solutions

Answer 315546 by rfer(12660) About Me  on 2011-06-11 20:59:20 (Show Source):
You can put this solution on YOUR website!
5x+4/9=7/9
5x=7/9-4/9
5x=3/9
x=(3/9)/5
x=3/9*1/5
x=3/45
x=1/15


Travel_Word_Problems/460059: If I am driving 50 miles per hour how long would it take to get 74 miles?
If I am driving 50 miles per hour how long would it take to get 44 miles?
1 solutions

Answer 315536 by rfer(12660) About Me  on 2011-06-11 19:52:05 (Show Source):
You can put this solution on YOUR website!
74/55=1.35 hrs=1 hr 21 min
44/55=0.8 hrs=48 minutes


Radicals/460036: square root of 20 plus the square root of 64 minus the square root of 125
1 solutions

Answer 315527 by rfer(12660) About Me  on 2011-06-11 18:36:10 (Show Source):
You can put this solution on YOUR website!
4.47+8-11.18=1.29


Sequences-and-series/460021: Identify the pattern and find the next term:
6, 1, 9, 5, 12, 9, 15,____
1 solutions

Answer 315524 by rfer(12660) About Me  on 2011-06-11 18:34:11 (Show Source):


Graphs/460034: i need help with the following:
Solve the inequality 2(3 - x) > 4 - 5x
Thank You
1 solutions

Answer 315522 by rfer(12660) About Me  on 2011-06-11 18:30:47 (Show Source):
You can put this solution on YOUR website!
6-2x > 4-5x
3x > -2
x > -2/3


Graphs/460038: I am starting to remoldle my yard and I want to spend no less than $6000 and no more tha $10000. Write an inqualities for this
1 solutions

Answer 315519 by rfer(12660) About Me  on 2011-06-11 18:27:35 (Show Source):
You can put this solution on YOUR website!
6000 =< x =< 10000


Percentage-and-ratio-word-problems/460002: If $35,600 was earned this year which was an increase of 14% over the previous year. What were the earnings last year?
1 solutions

Answer 315498 by rfer(12660) About Me  on 2011-06-11 16:50:49 (Show Source):
You can put this solution on YOUR website!
35600/1.14=$31,228.07


Quadratic_Equations/460010: (3/2+1/3)+(7/6-3/4)
1 solutions

Answer 315497 by rfer(12660) About Me  on 2011-06-11 16:47:06 (Show Source):
You can put this solution on YOUR website!
18/12+4/12+14/12-9/12=27/12=2 1/4


Linear-equations/459978: find the x and y intercepts and graph the equation plotting the intercepts. please show all of your work. 5x -7y = -35
1 solutions

Answer 315477 by rfer(12660) About Me  on 2011-06-11 14:02:17 (Show Source):
You can put this solution on YOUR website!
y int=5
(0,5)
x int=-7
(-7,0)


Quadratic_Equations/459979: For the following equation state the value of the discriminant and then describe the nature of the solutions 19x^2 +4x-13=0. What is the value of the discriminant and does it have one real solution two real solutions or two imaginary solutions?
1 solutions

Answer 315474 by rfer(12660) About Me  on 2011-06-11 13:59:50 (Show Source):
You can put this solution on YOUR website!
D=1004 under the radical
two real solutions


Percentage-and-ratio-word-problems/459857: if something was worth $ 4.3 but is now worth $ 33., what is the percent increase?
1 solutions

Answer 315473 by rfer(12660) About Me  on 2011-06-11 13:55:21 (Show Source):
You can put this solution on YOUR website!
33-4.3=28.7
28.7/4.3=6.67=667% increase