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 'nerdybill'

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, >>Next

 Geometry_Word_Problems/209166: This question is from textbook Prentice Hall Mathematics Algebra 2 the measures of an angle and its complement differ by twenty-two degrees. find the measures of the angles.1 solutions Answer 158127 by nerdybill(6962)   on 2009-08-27 21:39:05 (Show Source): You can put this solution on YOUR website!the measures of an angle and its complement differ by twenty-two degrees. find the measures of the angles. . If two angles are complementary, the sum of the two angles equals 90 degrees. . Let x = lesser of two angles then x+22 = greater of two angles . x + (x+22) = 90 2x + 22 = 90 2x = 68 x = 34 degrees . Other angle: x+22 = 34+22 = 56 degrees . The measure of the two angles are 34 and 56 degrees.
 Linear-equations/209062: 2y=x+4 need the slope and intersection1 solutions Answer 158023 by nerdybill(6962)   on 2009-08-27 13:51:19 (Show Source): You can put this solution on YOUR website!2y=x+4 need the slope and intersection . To determine the "slope" and the "y-intercept", you can manipulate the given equation into the "slope-intercept" form of a straight line: y = mx + b where m is the slope b is the y-intercept at (0,b) . To get it in the above form, simply divide both sides of the given equation by 2: 2y=x+4 y = (1/2)x + 2 This means: m (slope) is 1/2 and (0,2) is the y-intercept . To find the x-intercept, set y=0 and solve for 'x': 2y=x+4 2(0)=x+4 0=x+4 -4 = x therefore, (-4,0) is the x-intercept
 Equations/208959: One of the first mixtures of metals, called amalgams, used by dentists for tooth fillings consisted of 26.0 grams of silver, 10.8 grams of tin, 2.4 grams of copper, and 0.8 grams of zinc. How much silver is in a 25.0 gram sample of this analgam? thank you1 solutions Answer 157985 by nerdybill(6962)   on 2009-08-26 23:34:19 (Show Source): You can put this solution on YOUR website!26.0 grams of silver, 10.8 grams of tin, 2.4 grams of copper, and 0.8 grams of zinc . Total weight = 26.0 + 10.8 + 2.4 + 0.8 = 40 grams . Of the total weight, 26 grams is made up of silver Or 26/40 * 100 = 65% . So, if you have 25 grams of analgam, 65% would be silver: .65 * 25 = 16.25 grams
 logarithm/208905: Solve the equation for x. e^(ax) = Ce^(bx), where a is not equal to b1 solutions Answer 157960 by nerdybill(6962)   on 2009-08-26 19:57:27 (Show Source): You can put this solution on YOUR website!Solve the equation for x. e^(ax) = Ce^(bx), where a is not equal to b . Applying "log rules": e^(ax) = Ce^(bx) Divide both sides by e^(bx): e^(ax)/e^(bx) = C Rewriting the left side: e^(ax-bx) = C Take the ln of both sides: ax-bx = ln(C) Factor the left: x(a-b) = ln(C) Dividing we get: x = ln(C)/(a-b)
 Divisibility_and_Prime_Numbers/208896: i need help with this math problem i am so lost it says factor completely s^2-64 and the other says v^2-1/491 solutions Answer 157959 by nerdybill(6962)   on 2009-08-26 19:53:04 (Show Source): You can put this solution on YOUR website!factor completely s^2-64 and the other says v^2-1/49 . First one: s^2-64 Notice I can rewrite as: s^2-8^2 Now, you have a "difference of squares" -- which should automatically trigger: (s-8)(s+8) (this is completely factored) . Second one: Similar to the first: v^2-1/49 Can be rewritten as: v^2-(1/7)^2 Now, you have a "difference of squares" -- which should automatically trigger: (v-1/7)(v+1/7) (this is completely factored)
 expressions/208899: What is the number of gallons in 21 quarts?1 solutions Answer 157958 by nerdybill(6962)   on 2009-08-26 19:49:50 (Show Source): You can put this solution on YOUR website!What is the number of gallons in 21 quarts? . Since there are 4 quarts per gallon: . 21/4 = 5 and 1/4 gallons OR... 5.25 gallons
 Travel_Word_Problems/208704: respected sir, plz help me to solve this maths prob... 1] how many minutes does it take to travel 120 miles at 400 miles per hour? waiting for yur reply. thank u. regards Binita. 1 solutions Answer 157847 by nerdybill(6962)   on 2009-08-26 09:17:28 (Show Source): You can put this solution on YOUR website!how many minutes does it take to travel 120 miles at 400 miles per hour? . You will be applying the "distance formula": d = rt where d is distance r is rate or speed t is time . Let's start by solving: d = rt for 't': t = d/r . Plugging in the given values: t = 120/400 t = 3 hours Since the problem wants the answer in terms of minutes: t = 3 hours * 60 mins/hour = 180 minutes
 Mixture_Word_Problems/208662: This question is from textbook Tracey and Max determined that the vacation they would like to take for their anniversary would cost \$2250. If they put the money saved by making their own coffee into a vacation account,would there be enough money in eight months to take their vacations?1 solutions Answer 157846 by nerdybill(6962)   on 2009-08-26 09:11:54 (Show Source): You can put this solution on YOUR website!Tracey and Max determined that the vacation they would like to take for their anniversary would cost \$2250. If they put the money saved by making their own coffee into a vacation account,would there be enough money in eight months to take their vacations? . Previously, we found that Tracey and Max saves: \$180 per month if they make their own coffee . In 8 months, the will save: 8(180) = \$1440 . So, NO, they will not have enough for that vacation.
 Mixture_Word_Problems/208661: This question is from textbook If tracey and max make their own specialty blend of coffee.they estimate that it costs about \$1.00 for every 2 cups of coffee. Determine how much they are saving by making their own coffee 1 solutions Answer 157845 by nerdybill(6962)   on 2009-08-26 09:09:13 (Show Source): You can put this solution on YOUR website! If tracey and max make their own specialty blend of coffee.they estimate that it costs about \$1.00 for every 2 cups of coffee. Determine how much they are saving by making their own coffee . Previously, Max spends \$120 per month Tracey spends \$90 per month . To make their own: 1(30) = \$30 per month . Therefore, they will save: (120+90) - 30 = 210 - 30 = \$180 . That is, they will save \$180 per month if they make their own coffee instead of buying it.
 Mixture_Word_Problems/208659: This question is from textbook If max bought coffee at \$4.00 a cup on a average using a 30-day month,find the total amount use formulae m=4(30)1 solutions Answer 157844 by nerdybill(6962)   on 2009-08-26 09:06:14 (Show Source): You can put this solution on YOUR website!Assuming he buys a cup per day: 4(30)= \$120 He spends \$120 per month on coffee
 Mixture_Word_Problems/208658: This question is from textbook If tracey bought coffee at \$3.00 a cup using a 30-day month,find the total amount1 solutions Answer 157843 by nerdybill(6962)   on 2009-08-26 09:05:17 (Show Source): You can put this solution on YOUR website!Assuming she buys a cup per day: 3(30)= \$90 She spends \$90 per month on coffee
 Travel_Word_Problems/208614: 30. Two planes left an airport at noon. One flew east at a certain speed and the other flew west at twice the speed.The planes were 2700 mi apart in 3 h. How fast was each plane flying?1 solutions Answer 157842 by nerdybill(6962)   on 2009-08-26 08:54:13 (Show Source): You can put this solution on YOUR website!Two planes left an airport at noon. One flew east at a certain speed and the other flew west at twice the speed.The planes were 2700 mi apart in 3 h. How fast was each plane flying? . You will need to apply the "distance formula": d=rt where d is distance r is rate or speed t is time . Let x = speed of east bound plane then 2x = speed of west bound plane . 3x + 3(2x) = 2700 3x + 6x = 2700 9x = 2700 x = 300 mph (speed of east bound plane) . speed of west bound plane: 2x = 2(300) = 600 mph
 Proportions/208673: Rise and run. If the rise is 3/2 and the run is 5, then what is the ratio of the rise to the run?1 solutions Answer 157820 by nerdybill(6962)   on 2009-08-26 02:58:58 (Show Source): You can put this solution on YOUR website!The ratio of the rise over the run is the "slope": . slope = rise/run . In your case, since rise = 3/2 and run = 5 . then, slope = rise/run = (3/2)/5 = 3/10
 Proportions/208675: Rise and run. If the rise is 3/2 and the run is 5, then what is the ratio of the rise to the run?1 solutions Answer 157819 by nerdybill(6962)   on 2009-08-26 02:57:38 (Show Source): You can put this solution on YOUR website!Rise and run. If the rise is 3/2 and the run is 5, then what is the ratio of the rise to the run? . The ratio of the rise over the run is the "slope": . slope = rise/run . In your case, since rise = 3/2 and run = 5 . then, slope = rise/run = (3/2)/5 = 3/10 .
 Linear-systems/208611: -3xyz(squared) x=-4 y=-2 z=1\2 okay when i put this equation in my TI calculator i got 144 but when my teacher checked it he said it was wrong can you show me how to solve this problem? and what the correct answer would be PLEASE??????1 solutions Answer 157818 by nerdybill(6962)   on 2009-08-26 02:03:34 (Show Source): You can put this solution on YOUR website!-3xyz(squared) x=-4 y=-2 z=1\2 . Plugging in the given values: x=-4 y=-2 z=1\2 . order of operations (PEMDAS) says we deal with exponents first: Next, multiplication right to left:
 Functions/208663: Find the function value of f(x) = x to the third power. f(7) = ?1 solutions Answer 157817 by nerdybill(6962)   on 2009-08-26 01:58:31 (Show Source): You can put this solution on YOUR website!f(x) = x^3 . Therefore for x = 7: f(7) = 7^3 = 7*7*7 = 343
 Word_Problems_With_Coins/208666: My brain does not mix numbers and letters, but I'm trying to help my grandson with his summer homework. Here's one of two that he couldn't figure out. Altogether you have \$3.30. If you have 9 more nickels than dimes and 12 fewer quarters than nickels, how many of each do you have?1 solutions Answer 157816 by nerdybill(6962)   on 2009-08-26 01:56:38 (Show Source): You can put this solution on YOUR website!. Altogether you have \$3.30. If you have 9 more nickels than dimes and 12 fewer quarters than nickels, how many of each do you have? . Let x = number of dimes then x+9 = number of nickels x+9 -12 = x-3 = number of quarters . .05(x+9) + .10x + .25(x-3) = 3.30 .05x+.45 + .10x + .25x-.75 = 3.30 .40x-.30 = 3.30 .40x = 3.60 x = 3.60/.40 x = 9 (number of dimes) . number of nickels: x+9 = 9+9 = 18 . number of quarters: x-3 = 9-3 = 6
 Number-Line/208667: This is my grandson's other problem from his summer worksheet that he doesn't know how to do. Write a series of five decimal numbers that increase by 0.2 and add up to a total of 5. I think I've figured it out just by guessing (.60+.80+1.00+1.20+1.40) but I have no idea how to explain to him the right way to figure this out. There must be a logical solution other than trial and error or guessing. 1 solutions Answer 157815 by nerdybill(6962)   on 2009-08-26 01:52:03 (Show Source): You can put this solution on YOUR website! This is my grandson's other problem from his summer worksheet that he doesn't know how to do. Write a series of five decimal numbers that increase by 0.2 and add up to a total of 5. I think I've figured it out just by guessing (.60+.80+1.00+1.20+1.40) but I have no idea how to explain to him the right way to figure this out. There must be a logical solution other than trial and error or guessing. . Let x = first of five decimal numbers then x+.2 = second x+.4 = third x+.6 = fourth x+.8 = fifth . x + (x+0.2) + (x+0.4) + (x+0.6) + (x+0.8) = 5 Grouping like-terms: (x+x+x+x+x) + (0.2+0.4+0.6+0.8) = 5 5x + 2 = 5 5x = 5-2 5x = 3 x = 3/5 x = 0.6 (first decimal number) . The five numbers are indeed: .6, .8, 1, 1.2 and 1.4
 Problems-with-consecutive-odd-even-integers/208670: twice the greater of two consecutive odd integers is 13 less than three times the lesser. find the intergers.1 solutions Answer 157813 by nerdybill(6962)   on 2009-08-26 01:45:52 (Show Source): You can put this solution on YOUR website!twice the greater of two consecutive odd integers is 13 less than three times the lesser. find the intergers. . Let x = 1st consecutive odd integer then x+2 = greater consecutive odd integer . 2(x+2) = 3x-13 2x+4 = 3x-13 4 = x-13 17 = x . Greater integer: x+2 = 17+2 = 19 . Therefore, the two integers are 17 and 19
 Expressions-with-variables/208669: I have to write algebraic expression or equation to represent a phrase or sentence. 20% of 4001 solutions Answer 157812 by nerdybill(6962)   on 2009-08-26 01:43:05 (Show Source): You can put this solution on YOUR website!20% of 400 can be written as: .20(400)
 Functions/208644: This question is from textbook Advanced Algebra Consider the function y=x to the second power. what is the range?1 solutions Answer 157807 by nerdybill(6962)   on 2009-08-25 22:42:12 (Show Source): You can put this solution on YOUR website!Consider the function y=x to the second power. what is the range? . Since y can never be a negative, the range is: [0, +infinity) That is, All real number greater than or equal to 0.
 Equations/208626: A cheetah can run 112km/h over a 100-mile distance. What is this speed in meters per second? 1 solutions Answer 157796 by nerdybill(6962)   on 2009-08-25 21:54:00 (Show Source): You can put this solution on YOUR website! 112km/hr * 1/60 hr/min * 1/60 min/sec = 112/(3600) = 0.031 km/sec = 0.031 km/sec * 1000 m/km = 31 m/sec
 logarithm/208633: solve for x. log(base x)16 = 41 solutions Answer 157795 by nerdybill(6962)   on 2009-08-25 21:50:44 (Show Source): You can put this solution on YOUR website! Applying "log rules":
 Equations/208629: Solve for q: p squared q- 3q=141 solutions Answer 157793 by nerdybill(6962)   on 2009-08-25 21:37:38 (Show Source): You can put this solution on YOUR website! Solve for q: p squared q- 3q=14 . Factor out a 'q' on the left: Dividing both sides by:
 Expressions-with-variables/208388: How would I solve the equation listed below using the elimination method? I have tried, but I keep coming up with differnt answers. x+5y=29 -7x+4y=701 solutions Answer 157663 by nerdybill(6962)   on 2009-08-25 07:38:32 (Show Source): You can put this solution on YOUR website!x+5y=29 -7x+4y=70 . Multiply the top equation by 7 then combine: 7x+35y=203 -7x+4y=70 ---------- 39y = 273 y = 7 . Substitute the above back into equation 1 to solve for x: x+5y=29 x+5(7)=29 x+35=29 x = 29-35 x = -6 . Therefore, the solution is: (x,y) = (-6, 7)
 Miscellaneous_Word_Problems/208427: the price of a coat is representedd by (2x-5) dollars. Represent the amount a man paid for (5x-3) of these coats.1 solutions Answer 157662 by nerdybill(6962)   on 2009-08-25 07:33:54 (Show Source): You can put this solution on YOUR website! the price of a coat is representedd by (2x-5) dollars. Represent the amount a man paid for (5x-3) of these coats. . "amount paid" = "number of coats" * "price of a coat" . c(x) = (5x-3)(2x-5) c(x) = 10x^2-25X-6X+15 c(x) = 10x^2-31x+15 where c(x) is the amount paid
 Linear-equations/208429: Parallel and Perpendicular Slope Please help me solve this equation: Which lines are parallel? a.x=7 b.y=5/6x+8 c.y=5/6x-4 d.x=91 solutions Answer 157661 by nerdybill(6962)   on 2009-08-25 07:30:15 (Show Source): You can put this solution on YOUR website!Which lines are parallel? a.x=7 b.y=5/6x+8 c.y=5/6x-4 d.x=9 . 'a' and 'd' are parallel (both are vertical lines) AND 'b' and 'c' are parallel (by inspection, because of slope-intercept form y=mx+b -- both have the same slope of 5/6)
 Square-cubic-other-roots/208437: I got this wrong. (3x-2y)^2= (that's the equation) 9x^2-4y^2 (this is what i got by distributing the second power to everything in the parenthesis) The book said the answer was 9x^2+4y^2-12xy. Can you explain why I got it wrong and how to get the right answer?1 solutions Answer 157654 by nerdybill(6962)   on 2009-08-25 01:08:57 (Show Source): You can put this solution on YOUR website!(3x-2y)^2= (that's the equation) 9x^2-4y^2 (this is what i got by distributing the second power to everything in the parenthesis) The book said the answer was 9x^2+4y^2-12xy . (3x-2y)^2 = (3x-2y)(3x-2y) Applying FOIL: F: (first terms) (3x)(3x) = 9x^2 O: (outer terms) (3x)(-2y) = -6xy I: (inner terms) (-2y)(3x) = -6xy L: (last terms) (-2y)(-2y) = 4y^2 = 9x^2 - 6xy - 6xy + 4y^2 = 9x^2 - 12xy + 4y^2 After reordering: = 9x^2 + 4y^2 - 12xy
 Equations/208314: Solve for x. P(x-1)+7= r(x-4)1 solutions Answer 157585 by nerdybill(6962)   on 2009-08-24 16:45:08 (Show Source): You can put this solution on YOUR website!P(x-1)+7= r(x-4) Px-P+7= xr-4r Px-xr-P+7= -4r Px-xr+7= P-4r Px-xr= P-4r-7 x(P-r) = (P-4r-7) x = (P-4r-7)/(P-r)
 Equations/208313: Solve the formula for the indicated variable A=p+prt solve for p1 solutions Answer 157583 by nerdybill(6962)   on 2009-08-24 16:42:31 (Show Source): You can put this solution on YOUR website!A=p+prt Factoring the right: A=p(1+rt) Dividing both sides by (1+rt): A/(1+rt) = p
 Angles/208310: This question is from textbook geometry the means of two complementary angles are 16z-9 and 4z+3.find the measures of the angles1 solutions Answer 157582 by nerdybill(6962)   on 2009-08-24 16:40:57 (Show Source): You can put this solution on YOUR website! the means of two complementary angles are 16z-9 and 4z+3.find the measures of the angles . If two angles are "complementary", the sum of the two angles MUST equal 90 degrees. . (16z-9) + (4z+3) = 90 16z-9 + 4z+3 = 90 16z+4z+3-9 = 90 20z-6 = 90 20z = 96 z = 96/20 z = 24/5 . Therefore, the two angles are: 16z-9 = 16(24/5)-9 = 16(4.8)-9 = 76.8-9 = 67.8 degrees 4z+3 = 4(24/5)+3 = 4(4.8)+3 = 19.2+3 = 22.2 degrees