# 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 'elima'

elima answered: 1432 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, >>Next

 Word_Problems_With_Coins/183313: Stan has 52 quarters and nickels. He has three times many nickels as quarters. How much money does he have.1 solutions Answer 137662 by elima(1433)   on 2009-02-23 11:04:01 (Show Source): You can put this solution on YOUR website!Stan has 52 quarters and nickels. He has three times many nickels as quarters. How much money does he have. n + q = 52 3n=q substitute; n + 3n =52 4n=52 n=13 13+q=52 q=39 so he has 13 nickels and 39 quarters, now we need to find out how much money that actually is; nickel = .05 .05(13)=.65 quarters = .25 .25(39)=9.75 9.75 + .65 = \$10.40 :)
 percentage/183245: Ted typed 80%of his research paper before taking a break.If he typed 8pages,how many total pages are in the paper,how many pages dose he have to type? The YMCA wants to raise \$2500 for it's summer program for disadvantaged children. If the YMCA has already \$900,what percent of it's goal has been achieved? Of the 67million acres of landin Colorado, approximately 3.7 million acres is rural forestland. What percent is rural forestland? Forty-four percent of Americans use online travel sites to book hotel or airline reservations.If 400 people need to make airline or hotel reservations, how many would be expected to use online travel sites? The earth is covered by appoximately 360 million km2 of water. If the total surface area is 510 million km2,what percent is water? Round to the nearest tenth of a percent.1 solutions Answer 137661 by elima(1433)   on 2009-02-23 10:54:24 (Show Source): You can put this solution on YOUR website!Ted typed 80%of his research paper before taking a break.If he typed 8pages,how many total pages are in the paper,how many pages dose he have to type? .8x=8 x=10 =================== The YMCA wants to raise \$2500 for it's summer program for disadvantaged children. If the YMCA has already \$900,what percent of it's goal has been achieved? 2500x=900 x=36% ========================= Of the 67million acres of landin Colorado, approximately 3.7 million acres is rural forestland. What percent is rural forestland? 67x=3.7 x=5.5% ========================= Forty-four percent of Americans use online travel sites to book hotel or airline reservations.If 400 people need to make airline or hotel reservations, how many would be expected to use online travel sites? 400(44%)=176 ============================ The earth is covered by appoximately 360 million km2 of water. If the total surface area is 510 million km2,what percent is water? Round to the nearest tenth of a percent. 510x=360 x=71% :)
 Quadratic_Equations/180707: Linear Systems 1. Solve by graphing. Check each solution. a) y=x-3 b) y=2x-1 c) x+3y=2 d) 3x+2y=6 y=3-x y=-x+5 x-y=6 y=4-x Thank you very much pleaseeeeeeeeeeeeee1 solutions Answer 135502 by elima(1433)   on 2009-02-07 16:01:29 (Show Source): You can put this solution on YOUR website!1. Solve by graphing. Check each solution. a) y=x-3 b) y=2x-1 c) x+3y=2 d) 3x+2y=6 y=3-x y=-x+5 x-y=6 y=4-x =========================================== a)y=x-3 slope = 1/1 y-intercept = -3 ========================================== b) y=2x-1 slope = 2/1 y-intercept = -1 =========================================== c) x+3y=2 First put this in slope-intercept form; y=mx+b subtract each side by x; 3y=-x+2 now divide each side by 3; y = -1/3x + 2/3 slope= -1/2 y-intercept = 2/3 Think you can do the rest? Just remember, if the equation is not in slope-intercept form, you need to put it in that form. Then identify the slope and y-intercept, plot the point on the y-axis and use the slope to find the next point, then draw the line. :)
 Linear-equations/180299: 7x+3y=6 3x+2y=-11 solutions Answer 135216 by elima(1433)   on 2009-02-05 13:41:46 (Show Source): You can put this solution on YOUR website!7x+3y=6 3x+2y=-1 First write each equation in slope-intercept form; 7x+3y=6 3y=-7x+6 y = 3x+2y=-1 2y=-3x-1 y = Now graph:
 Linear-equations/180273: Find the equation of a line that goes through the point ( 3 , -5 ) and has a slope of 2. Write your answer in slope intercept form (that is when the equation is simplified and the y is isolated1 solutions Answer 135214 by elima(1433)   on 2009-02-05 13:22:19 (Show Source): You can put this solution on YOUR website!y = mx + b since we know the slope and one point, substitute those in the equation to find b; -5 = 2(3) + b -5 = 6 + b -5 - 6 = b -11 = b so the equation would be; y = 2x - 11 :)
 Surface-area/180198: This question is from textbook glencoe Geometry the surface area of a cone is 293.2 square feet and the radius is 6.1 feet what is the slant height1 solutions Answer 135208 by elima(1433)   on 2009-02-05 13:04:04 (Show Source): You can put this solution on YOUR website!SA= 293.2 = multiply; 293.2 = 116.84 + 19.15L subtract 116.84 from each side; 293.2 - 116.84 = 19.15L 176.36 = 19.15L divide each side by 19.15; 9.21 = L :)
 Polygons/175281: A regular polygon has an interior angle measure of 160 degrees. How many sides does the polygon have?1 solutions Answer 130490 by elima(1433)   on 2009-01-07 13:49:30 (Show Source): You can put this solution on YOUR website! multiply each side by n; (n-2)180=160n 180n-360=160n 180n-160n-360 20n=360 divide each side by 20; n=18 so the number of side = 18 :)
 Polynomials-and-rational-expressions/173488: 5x to the 2nd power y to the 3rd power-20xy to the 2nd power1 solutions Answer 128855 by elima(1433)   on 2008-12-18 13:01:35 (Show Source): You can put this solution on YOUR website! Factor out what is common;
 Linear-systems/173709: Solve by addition or substitution. 3x + 5y = 2 2x + 5y = -21 solutions Answer 128606 by elima(1433)   on 2008-12-16 20:10:54 (Show Source): You can put this solution on YOUR website!We will solve this by addition; 3x + 5y = 2 (-1)2x + 5y = -2 ==================== 3x +5y = 2 -2x -5y = 2 ------------ x=4 Now that we have our x lets plug that in to find y; 3(4)+5y=2 12 +5y =2 5y = -10 y = -2 ============= :)
 Systems-of-equations/170331: This question is from textbook Introductory Algebra Solve using the substitution method y = 2x - 5 3x + y = 151 solutions Answer 125884 by elima(1433)   on 2008-12-01 14:28:05 (Show Source): You can put this solution on YOUR website!Since you are already given what y equals, we will plug that into the second equation to find x; y = 2x - 5 3x + y = 15 =================== 3x + (2x - 5) = 15 5x - 5 = 15 5x = 20 x = 4 Now we have x, lets plug that into the equation to find y; 3(4) + y =15 12 + y =15 y = 15-12 y = 3 :)
 Percentage-and-ratio-word-problems/169560: I thank you in advance for your assistance. I have not done any problems in a while! the problem is: Mr. Jones had to interview a total of 63 households in his assignment. He has already finished 28. what percentage of the households in his assignments has he finished? (round to the nearest tenth of a percent)1 solutions Answer 124979 by elima(1433)   on 2008-11-25 10:30:11 (Show Source): You can put this solution on YOUR website!total= 63; He has finished 28; What we are asked to find is the percent - that is our variable = P We have; 28 = 63P divide each side by 63; .4444=P rounded to nearest tenth; P=.4 :)
 Graphs/169064: x+3y=23 3x-2y=31 solutions Answer 124738 by elima(1433)   on 2008-11-23 12:51:46 (Show Source): You can put this solution on YOUR website!First put them in slope-intercept form; x+3y=23 3y=-x+23 3x-2y=3 -2y=-3x+3
 Geometry_proofs/167277: I DON'T UNDERSTAND PROOFS AT ALL. we're doing them in my geometry class and i'm like.. duh. can't do it. i dont know the reasons and i dont know how to find anything to get reasons and i really need help cause i have like a 20 in this class because of stupid proofs...1 solutions Answer 123228 by elima(1433)   on 2008-11-12 19:29:53 (Show Source): You can put this solution on YOUR website!I'll try to help; A proof is a logical argument to convince someone that a statement is true. There are steps you will try and follow when proving something, 1. Write information you've been given as true. 2. Write what you need to prove. 3. Draw a diagram and mark given information. 4. Plan how to get from the given to the prove. 5. Add to the diagram if needed 6. Set out logical sequence of statements and reasons beginning with what you know and ending with what you've been asked to prove (postulates, definitions, theorems, etc).
 Miscellaneous_Word_Problems/167180: A die is rolled twice. What is the probability of rolling a number less than 4 followed by a number less than 3?1 solutions Answer 123221 by elima(1433)   on 2008-11-12 18:58:49 (Show Source): You can put this solution on YOUR website!One die = 6 sides Since one event does not depend on the second this event would be independent. P(<4, then <3) :)
 Miscellaneous_Word_Problems/167176: If two dice are rolled, what is the probability that the resulting sum is less than 5?1 solutions Answer 123220 by elima(1433)   on 2008-11-12 18:50:59 (Show Source): You can put this solution on YOUR website! Two dice = 12 sides number of favorable outcomes = 1 + 1, 1 + 2, 1 + 3, 2 + 2; any other combination gives a sum greater than 5; :)
 Linear_Algebra/166353: Solve by elimination. -3+2y-5z=-3 3x-y+3z=4 3x+5y-8z=61 solutions Answer 122642 by elima(1433)   on 2008-11-07 16:03:51 (Show Source): You can put this solution on YOUR website!-3+2y-5z=-3 3x-y+3z=4 3x+5y-8z=6 We will take two of the equations, add them together to eliminate a variable; -3x+2y-5z=-3 + 3x-y+3z=4 ------------ y-2z=1 ================= Now take two other equations and add together to eliminate a variable; -3x+2y-5z=-3 + 3x+5y-8z=6 ------------- 7y-13z=3 =========================== Now add these two together to eliminate a variable;put first we will need to multiply the first equation by -7 so we will be able to eliminate; -7(y-2z=1) -7y+14z=-7 Now we add; -7y+14z=-7 + 7y-13z=3 ----------- z=-4 ============================= Now we have our z, so we use that in one of the new equations to find y; y-2(-4)=1 y+8=1 y=-7 ================================ We have our y and z so lets plug those values into one of the original equations to find x; 3x-(-7)+3(-4)=4 3x+7-12=4 3x-5=4 3x=9 x=3 Hope you got all of that :)
 Expressions-with-variables/166337: I have a test at my college on monday and I was wondering if you could please explain to me how to solve the equation. 2zx(2)y=18 where x=1,z=y1 solutions Answer 122635 by elima(1433)   on 2008-11-07 15:42:47 (Show Source): You can put this solution on YOUR website!I am assuming that (2) is actually an exponent? 2zx(2)y=18 where x=1,z=y so we rewrite the equation with the information given, we use 1 in place of our x and y in place of z; divide each side by 2; take the square root of each side; we end with; y=9 Hope this is clear and I helped. :)
 Linear-equations/166327: find an equation of the line containing (-2,3) and perpendicular to the line 2x+y=61 solutions Answer 122630 by elima(1433)   on 2008-11-07 15:35:18 (Show Source): You can put this solution on YOUR website!2x+y=6 First put this in slope-intercept form; y=-2x+6 ===================== The slope of perpendicular lines are negative reciprocals, so the slope for the new equation would be; 1/2 so far we have; y=1/2 + b now lets find b; Use the points given replacing the x and y; 3 = 1/2(-2)+b 3 = -1 + b 4 = b ============== The new equation; y = 1/2x + 4 :) :)
 Linear-systems/166181: 2x+y=7 y=mx+b1 solutions Answer 122449 by elima(1433)   on 2008-11-06 09:18:07 (Show Source): You can put this solution on YOUR website!You need to post the directions, I am not sure what it is you need to do. Do you need to graph? Put in slope-intercept form? slope-intercept form; y=-2x+7
 Geometry_proofs/166141: This question is from textbook Properties from Algebra and Proof complete proof for the following: 26. If 4 - x = 10, then x = -6 1 solutions Answer 122448 by elima(1433)   on 2008-11-06 09:13:37 (Show Source): You can put this solution on YOUR website!4 - x = 10, then x = -6 -x=10-4 -x=6 x=-6 True :)
 Finance/166030: This question is from textbook Algebra1 Joe has \$6500.00 to invest. Part of this will be invested in a savings account yielding 4% and part in a municipal bond yielding 7.5%. If he earns \$438.50 each year in interest, how much will be invested in each account?1 solutions Answer 122365 by elima(1433)   on 2008-11-05 19:18:12 (Show Source): You can put this solution on YOUR website!first account = .075x second account = .04(6500-x) 438.5 = .075x + 260 - .04x 438.5 = .035x + 260 178.5 = .035x 5100 = x ================== first account = \$5100.00 second account = 6500 - 5100 = \$1400.00 :)
 Travel_Word_Problems/166009: two cars started from the same place at the same time and traveled in opposite directions. at the end of 6 hours, they were 420 miles apart. if the average rate of the slow car exceeded 1/2 of the average rate of the fast car by 13 mph, find the rate of each car.1 solutions Answer 122364 by elima(1433)   on 2008-11-05 19:09:01 (Show Source): You can put this solution on YOUR website!fast car = r slow car= 1/2r+13 d=rt 420=6(r + 1/2r + 13) 420 = 6r + 3r + 78 342=9r 38=r ================= fast car rate = 38 slow car rate = 1/2(38)(6) slow car = 192 :)
 Linear-equations/165997: This question is from textbook Elementary and Intermediate Algebra, 3eElementary and Intermediate Algebra, 3e ISBN: 9780073533490 Author: Mark Dugopolski Citation Generator copyright © 2009 The McGraw-Hill Companies Page 251 number 19 Sketch the graph of each equation Y>3x-51 solutions Answer 122362 by elima(1433)   on 2008-11-05 18:54:18 (Show Source): You can put this solution on YOUR website!When you graph this, the line will be dashed and you will shade the area under(right side)the line. :) Y>3x-5
 Numeric_Fractions/165190: 94. Marginal revenue. A defense attorney charges her client \$4,000 plus \$120 per hour. The formula R = 120n + 4000 gives her revenue in dollars for n hours of work. What is her revenue for 100 hours of work? What is her revenue for 101 hours of work? By how much did the one extra hour of work increase the revenue? (The increase in revenue is called the marginal revenue for the 101st hour.) 1 solutions Answer 121847 by elima(1433)   on 2008-11-02 10:48:39 (Show Source): You can put this solution on YOUR website!R = 120n + 4000 For 100 hours of work? R=120(100)+4000=12000+4000=16000 For 101 hours of work? R=120(101)+4000 = 12120+4000 = 16120 Increase = 120 :)
 Graphs/165173: Solve the system of equations using the addition (elimination) method. If the answer is a unique solution, present it as an ordered pair: (x, y). If not, specify whether the answer is “no solution” or “infinitely many solutions.” 4x – 3y = 1 -12x + 9y = 5 1 solutions Answer 121844 by elima(1433)   on 2008-11-02 10:32:09 (Show Source): You can put this solution on YOUR website!4x – 3y = 1 -12x + 9y = 5 ================== (3)4x-3y=1 ================== 12x+9y=3 -12x+9y=5 ---------- No solution, both variables will be eliminated. :)
 expressions/165170: Find the slope of the line that passes through the points (-3, -5) and (-5, 1). 1 solutions Answer 121771 by elima(1433)   on 2008-11-01 15:32:47 (Show Source): You can put this solution on YOUR website!(-3, -5), (-5, 1) slope= :)
 Linear-equations/164940: 5. Fill in the chart given this linear equation: 2x + y = 42. Type all your work below the chart. x y -2 -1 0 1 2 1 solutions Answer 121654 by elima(1433)   on 2008-10-31 12:58:14 (Show Source): You can put this solution on YOUR website!Is all you need to do is plug the numbers given as your x and solve for y; x | y -2 | -1 | 0 | 1 | 2 | 2x + y = 42 2(-2)+y=42 -4+y=42 y=42+4 y=46 ============== 2x + y = 42 2(-1)+y=42 -2+y=42 y=42+2 y=44 ================ 2x + y = 42 2(0)+y=42 y=42 ============== 2x + y = 42 2(1)+y=42 2+y=42 y=42-2 y=40 ============ 2x + y = 42 2(2)+y=42 4+y=42 y=38 :)
 Problems-with-consecutive-odd-even-integers/164095: the product of two consecutive even integers is 1681 solutions Answer 120907 by elima(1433)   on 2008-10-26 15:53:18 (Show Source): You can put this solution on YOUR website!1st integer = x 2nd integer = x+2 ====================== x(x+2)=168 (x+14)(x-12)=0 x+14=0 x=-14 x-12=0 x=12 ================= So we end up with 2 possibilities; x = 12 or x = -14 Now we need our second; x + 2 = 12+2=14 x+2 = -14+2=-12 ==================== When x = 12, the second integer = 14 When x = -14, second integer = -12 :)
 Numbers_Word_Problems/164092: The length of a rectangle is 3 feet less than twice the width. If the perimeter is 54ft. find the dimensions.1 solutions Answer 120905 by elima(1433)   on 2008-10-26 15:36:28 (Show Source): You can put this solution on YOUR website!The length of a rectangle is 3 feet less than twice the width. If the perimeter is 54ft. find the dimensions. L = 2W-3 W= W 2L + 2W = 54 2(2w-3)+2W=54 4W-6+2W=54 6W=60 W=10 L=2(10)-3 L=20-3 = 17 check; 2(17)+2(10)=54 34+20=54 :)
 Numbers_Word_Problems/164082: An 18in piece of wire is cut into 3 peices. The third piece is 4 inches more than half the second piece and the first piece is 2 inches shorter than the third piece. Find the length of these three pieces.1 solutions Answer 120904 by elima(1433)   on 2008-10-26 15:14:34 (Show Source): You can put this solution on YOUR website!x = length of the pieces 2nd piece = x 3rd piece = 1/2x+4 1st piece = 3rd piece - 2 = (1/2x+4)-2 Now lets add the pieces together and have them = 18; x + 1/2x+4 + (1/2x+4)-2 =18 x+ x+4+2=18 2x+6=18 2x=12 x=6 Now we have the length of the 2nd, lets plug this into the others to find their length; 3rd = 1/2(6)+4 3rd = 3+4= 7 1st = 7-2 = 5 check; 5+6=11+7=18 :)