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 'edjones'

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, >>Next

 Square-cubic-other-roots/241792: u-3(square root of u)-10=0 Hint: let x= square root of u, so x squared = u1 solutions Answer 177087 by edjones(7569)   on 2009-11-22 19:07:30 (Show Source): You can put this solution on YOUR website!u-3sqrt(u)-10=0 u-10=3sqrt(u) u^2-20u+100=9u square each side. u^2-29u+100=0 (u-25)(u-4)=0 u=25, u=4 u=25 is the only answer. If you check u=4 you will find that it is extraneous. . Ed
 Coordinate-system/241791: please help me in graphing parabolas y=x^2 - 21 solutions Answer 177082 by edjones(7569)   on 2009-11-22 18:53:13 (Show Source): You can put this solution on YOUR website!To graph it you don't have to figure out the problem. Create a table with x and y at the top. put in a value for x and calculate the value for y. put a dot on graph paper for those values. Use small whole numbers for x values and don't forget negative values for x and x=zero. pretty soon you'll have a parabola. . Ed
 Numbers_Word_Problems/241464: how many integers greater than 10 and less than one hundred are increased by nine when their digits are reversed1 solutions Answer 176935 by edjones(7569)   on 2009-11-22 09:22:00 (Show Source): You can put this solution on YOUR website!8 12, 23, 34, 45, 56, 67, 78, 89. . Ed
 percentage/241528: What is 33 1/3 of 35001 solutions Answer 176927 by edjones(7569)   on 2009-11-22 08:44:26 (Show Source): You can put this solution on YOUR website!100/3 * 3500 = 350000/3
 Linear-equations/241534: can someone please tell me the method to solving this linear equation? 3n-1/5 + n/2 = 2 / means over as in 5 over 10 (5 divided by 10)1 solutions Answer 176925 by edjones(7569)   on 2009-11-22 08:41:13 (Show Source): You can put this solution on YOUR website!3n-1/5 + n/2 = 2 30n-2+5n=20 multiply each side by 10 (LCM) to eliminate fractions. 35n=22 n=22/35 . Ed
 Quadratic_Equations/241543: Here's my question. Graph each parabola. Identify the vertex, intercepts, and the maximum or minimum y-value. f(x) = 16 – x^2 Once I figure out the problem then I should be able to graph it I hope. Thanks.1 solutions Answer 176922 by edjones(7569)   on 2009-11-22 08:36:10 (Show Source): You can put this solution on YOUR website!To graph it you don't have to figure out the problem. Replace f(x) with y. Create a table with x and y at the top. put in a value for x and calculate the value for y. put a dot on graph paper for those values. Use small whole numbers for x values and don't forget negative values for x and x=zero. pretty soon you'll have a parabola. . Ed
 Equations/241548: How do I Factor Completely factory 4x^4-16x^3+32x^21 solutions Answer 176918 by edjones(7569)   on 2009-11-22 08:24:34 (Show Source): You can put this solution on YOUR website!4x^4-16x^3+32x^2 4x^2(x^2-4x+8) . Ed
 Equations/241549: I need help with this problem Multiply (-3x)^2 (4x^6)^2=1 solutions Answer 176917 by edjones(7569)   on 2009-11-22 08:22:51 (Show Source): You can put this solution on YOUR website! (-3x)^2 (4x^6)^2 =9x^2 * 16x^12 powers of powers are multiplied. =144x^14 powers * powers are added. . Ed
 Geometry_Word_Problems/241555: The ratio of the area of two circle is 16/9. What is the ratio of their circumference? a. 4/3 b. 16/9 c. 32/18 d. 256/811 solutions Answer 176916 by edjones(7569)   on 2009-11-22 08:17:07 (Show Source): You can put this solution on YOUR website!pi*r^2/pi*r^2=16/9 pi cancels out. area/area r/r=4/3 sqrt of each side 2pi*r/2p*r=4/3 [2pi cancels out] circumf/circumf . Ed
 Linear_Equations_And_Systems_Word_Problems/241564: The base of an iscosceles triangle is 4/3cm. The perimeter of the triangle is 4 2/15cm. What is the length of either of the remaining sides?1 solutions Answer 176913 by edjones(7569)   on 2009-11-22 08:05:35 (Show Source): You can put this solution on YOUR website!4/3=20/15, 4 2/15=62/15 62/15 - 20/15 = 42/15 42/15 * 1/2 = 21/15 = 7/5 cm . Ed
 Rational-functions/241530: 1019 is what percentage of 35001 solutions Answer 176902 by edjones(7569)   on 2009-11-22 00:50:35 (Show Source): You can put this solution on YOUR website!1019/3500 =.2911...=29.11% . Ed
 logarithm/241460: 3^(x^2+1)=243 solve for x. please explain1 solutions Answer 176849 by edjones(7569)   on 2009-11-21 19:10:17 (Show Source): You can put this solution on YOUR website!3^(x^2+1)=243 3^(x^2+1)=3^5 log[3](3^(x^2+1)=log[3](3^5) x^2+1=5 x^2=4 x=2, x=-2 . Ed
 Radicals/241468: Simplify: (square root of 3y^2)^61 solutions Answer 176837 by edjones(7569)   on 2009-11-21 18:45:01 (Show Source): You can put this solution on YOUR website!sqrt(3y^2)^6 (3^(1/2)y)^6 3^3y^6 27y^6 . Ed
 logarithm/241397: how to solve: 4^(3x-1)=3^(x-1) i can't rember how to solve for x. i am lost.1 solutions Answer 176789 by edjones(7569)   on 2009-11-21 15:42:56 (Show Source): You can put this solution on YOUR website!4^(3x-1)=3^(x-1) log[4](4^3x-1)=log[3](3^(x-1))/log[3](4) Change of base formula from 3 to 4 on the right side. 3x-1=(x-1)/1.2619 3.7856x-1.2619=x-1 2.7856x=.2619 x=.094... . Ed
 Probability-and-statistics/241382: Suppose that the probability that a new medication will cause a bad side effect is 0.03. If this medication is given to 150 people, what is the probability that more than three of them will experience a bad side effect? Round answer to 4 decimal places. I think I know how to compute for "exactly three students," but I cannot figure out how to do "more than three students" Here's how I approached "exactly three": p = 0.03, q = 1 - p = 0.97, n = 150 P(r, n) = nCr (p)^r * (q)^(n - r) P(3, 150) = 150C3 * 0.03^3 * 0.97^147 = 0.1691 Since I am trying to figure out how to do these types of problems on my own, please include the steps. Thank you! 1 solutions Answer 176783 by edjones(7569)   on 2009-11-21 15:00:49 (Show Source): You can put this solution on YOUR website!You are correct so far as you have gone. Now do the same procedure for exactly 2, 1 and 0 students. Find the sum of the 4 probabilities and subtract it from 1 and you have your answer. . Ed
 Inequalities/241389: How do I solve: 7y-12 is less than 8y+51 solutions Answer 176782 by edjones(7569)   on 2009-11-21 14:47:11 (Show Source): You can put this solution on YOUR website!7y-12 < 8y+5 add -7y-5 to each side. y>-17 . Ed
 Linear-equations/241386: x + y =5 2x - y =4 -2x +-2y = -10 2x-y =4 2x - y = 4 2x -2 =4 3y -6 __ ___ 3 = 3 y = -2 __ then lost - is this right so far and can you show me how to do problem?1 solutions Answer 176781 by edjones(7569)   on 2009-11-21 14:39:28 (Show Source): You can put this solution on YOUR website!x + y =5 2x - y =4 . x=5-y 2(5-y)-y=4 Replace x with 5-y. 10-2y-y=4 -3y=-6 y=2 x=3 . Ed
 Mixture_Word_Problems/241234: Could someone please help me with this mixture problem? I have been pouring over it for two days (total of over 4 hours), and have tried various methods none of them yielding the correct answer. A mechanic has 363 gallons of gasoline and 17 gallons of oil to make gas/oil mixtures. He wants one mixture to be 6% oil and the other mixture to be 2.5% oil. If he wants to use all of the gas and oil, how many gallons of gas and oil are in each of the resulting mixtures?1 solutions Answer 176699 by edjones(7569)   on 2009-11-21 00:36:58 (Show Source): You can put this solution on YOUR website!Let x=gals of gas required to make a .025 mixture. Let y=gals of oil required to make a .025 mixture. . A) y/(x+y)=.025 B) (17-y)/(363-x+17-y)=.06 . A) y=.025x+.025y .975y=.025x y=.0256x . B) (17-.0256x)/(380-x-.0256x)=.06 17-.0256x=22.8-.0615x .0359x=5.8 x=161.56 gal . A) y/(161.56+y)=.025 y=4.039+.025y .975y=4.039 y=4.142 gal It wont be exact because of rounding errors. . Ed
 Permutations/241104: an octagon has 8 sides. How many diagnals does an octagon have?? my answer is 28 diagnals.1 solutions Answer 176612 by edjones(7569)   on 2009-11-20 16:04:59 (Show Source): You can put this solution on YOUR website!20 There are 5 diagonals for each point. 8*5=40. Half are repetitions. 40/2=20 . Ed
 Square-cubic-other-roots/241151: the square root of 49 is how much less than four squared?1 solutions Answer 176609 by edjones(7569)   on 2009-11-20 16:00:27 (Show Source): You can put this solution on YOUR website!sqrt(49)=7 4^2=16 16-7=9 . Ed
 Miscellaneous_Word_Problems/241163: 4 more than 3 how would i right that 4+3?1 solutions Answer 176608 by edjones(7569)   on 2009-11-20 15:58:14 (Show Source): You can put this solution on YOUR website!3+4
 Geometry_Word_Problems/241053: The ratio of the diameters of two circles is 1:4. The ratio of their radii is A) 1:2 B) 1:4 C) 1:8 D) 1:161 solutions Answer 176536 by edjones(7569)   on 2009-11-20 04:24:58 (Show Source):
 Systems-of-equations/240941: solve y=x+3 y=2x+41 solutions Answer 176502 by edjones(7569)   on 2009-11-19 20:03:05 (Show Source): You can put this solution on YOUR website!y=x+3 y=2x+4 2x+4=x+3 x=-1 y=2 . Ed