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 Average/309823: If the average of three numbers is V. If one of the numbers is Z and another is Y, what is the remaining number? 1 solutions Answer 221593 by ankor@dixie-net.com(15652)   on 2010-05-30 13:21:11 (Show Source): You can put this solution on YOUR website!If the average of three numbers is V. If one of the numbers is Z and another is Y, what is the remaining number? : Let x = remaining number : = V Multiply both sides by 3 x + y + z = 3V x = 3V - y - z, is the remaining number
 Polynomials-and-rational-expressions/309783: one of two supplementary angles is 4degrees more thatn one -third of the other angle . find the measure of each of the angle 1 solutions Answer 221572 by ankor@dixie-net.com(15652)   on 2010-05-30 10:42:17 (Show Source): You can put this solution on YOUR website!one of two supplementary angles is 4 degrees more than one -third of the other angle . find the measure of each of the angle : Let x = one angle then (180-x) = the other angle : x = (180 - x) + 4 Multiply both sides by 3 3x = 180 - x + 3(4) 3x = 180 - x + 12 3x + x = 192 4x = 192 x = x = 48 degrees then 180 - 48 = 132 degrees is the other angle : : See if that fits in the statement; "one of two supplementary angles is 4 degrees more than one-third of the other" 48 = (132) + 4 48 = 44 + 4
 Equations/309748: solve 5 raised to x+2=12?1 solutions Answer 221571 by ankor@dixie-net.com(15652)   on 2010-05-30 10:23:31 (Show Source): You can put this solution on YOUR website!solve 5 raised to x+2=12? Use logs here log equiv of exponents (x+2)log(5) = log(12) x + 2 = using a calc x + 2 = 1.544 : x = 1.544 - 2 ; x = -.456 : : Check on a calc enter 5^(-.456+2) = 12.00
 Rate-of-work-word-problems/309801: If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa, and Tom worked together to complete it? What equation do you need to find the answer?1 solutions Answer 221570 by ankor@dixie-net.com(15652)   on 2010-05-30 10:12:52 (Show Source): You can put this solution on YOUR website!If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa, and Tom worked together to complete it? What equation do you need to find the answer? : Let x = time required when working together Let the completed job = 1 : The equation + + = 1
 Rate-of-work-word-problems/309762: A completes one work in20 days. B cmpletes the same work in 25 days while C completes the same in 30 days. If intially A started the work and after 4 days he quit it. Next B carry forward the work & he copleted the half of the remaining work then how in how many days the C will cmplete the remaining work?1 solutions Answer 221569 by ankor@dixie-net.com(15652)   on 2010-05-30 10:09:16 (Show Source): You can put this solution on YOUR website!A completes one work in 20 days. B cmpletes the same work in 25 days while C completes the same in 30 days. : If initially A started the work and after 4 days he quits it. Next B carry forward the work & he completed the half of the remaining work then how in how many days the C will complete the remaining work? : Let the completed work = 1 : A does = ; remains : B does * = remains : = cross multiply 5C = 60 C = C = 12 days to complete it : : Check A does B does C does ----------------- total 1
 Rectangles/309709: im trying to figure out how to get The width of a rectangular feed lot is 8 m less than the length. The area is 20 m squared . Find the length and the width. i thought it would be (8-m)((20-m)squared1 solutions Answer 221502 by ankor@dixie-net.com(15652)   on 2010-05-29 21:57:40 (Show Source): You can put this solution on YOUR website!The width of a rectangular feed lot is 8 m less than the length. The area is 20 m squared . Find the length and the width. : "The width of a rectangular feed lot is 8 m less than the length." W = (L-8) : L * W = 20 Replace W with (L-8), find L L * (L-8) = 20 A quadratic equation L^2 - 8L - 20 = 0 factors to (L-10)*L+2) = 0 The positive solution is what we want here L = 10 m is the length then W = 10 - 8 W = 2 m is the width
 Quadratic_Equations/309682: N(x)=0.4x^2+8.8x+11 x=days Peak sales of tickets will be on what day and how many tickets are sold that day?1 solutions Answer 221491 by ankor@dixie-net.com(15652)   on 2010-05-29 19:02:48 (Show Source): You can put this solution on YOUR website!N(x)=-0.4x^2+8.8x+11 (coefficient of x^2 has to be negative) x=days Peak sales of tickets will be on what day and how many tickets are sold that day? : This is a quadratic equation, find the axis of symmetry to find the day of max sales Use the formula: x = -b/(2a), in this equation a=-.4, b=8.8 x = x = x = +11th day will be peak sales : Find the no. of sales on that day N(x) = -0.4x^2 + 8.8x + 11 Replace x with 11 N(11) = -0.4(11^2) + 8.8(11) + 11 N(11) = -0.4(121) + 96.8 + 11 N(11) = -48.4 + 96.8 + 11 N(11) = 59.4 ~ 59 tickets sold on the 11th day
 Volume/309470: The top of a right rectangular box has an area of 88cm^2 The sides have areas 32cm^2 and 44cm^2 What are the dimensions of the box?1 solutions Answer 221455 by ankor@dixie-net.com(15652)   on 2010-05-29 15:46:21 (Show Source): You can put this solution on YOUR website!The top of a right rectangular box has an area of 88cm^2 The sides have areas 32cm^2 and 44cm^2 What are the dimensions of the box? : L*W = 88 : L*H = 32 L = : W*H = 44 W = : Substitute for L & W in the 1st equation * = 88 = 88 88H^2 = 1408 H^2 = H^2 = 16 H = H = 4 cm is the height : L = L = L = 8 cm is the length : I'll let you find W using W =
 Age_Word_Problems/309626: Mary (m) is 4 years older than Rico (r). Ten years ago Mary was 3 times as old as Rico was then. a) how old are they now? b) determine if answer is correct by checking that it satisfies the conditions of the problem I've got r = 4 = m and have to subtract 10 years from both and multiply both by 3? 3(r-10) = m -10 3r - 30 = m -10 m = 3r - 20 r + 4 = 3r - 4 + r = -20 + 3r (subtract 3r from both sides) 4 + -2r = -20 (subtract 4 from both sides) -2r = -24 (divide both by -2) gives the solution of 12? so if I was solving for r, then that is Rico's age 10 years ago?? He would be 22 now and if 4 years older, Mary would be 26? This can't be right if 10 years ago she was 3 times his age. 1 solutions Answer 221444 by ankor@dixie-net.com(15652)   on 2010-05-29 12:56:06 (Show Source): You can put this solution on YOUR website!Mary (m) is 4 years older than Rico (r). Write an equation for this statement first: m = r+4 Ten years ago Mary was 3 times as old as Rico was then. a) how old are they now? I've got r = 4 = m?????? and have to subtract 10 years from both and multiply both by 3? 3(r-10) = m - 10 3r - 30 = m -10 Correct up to here, now 3r = m - 10 + 30 3r = m + 20 Replace m with (r+4) 3r = (r+4) + 20 3r - r = 24 2r = 24 r = r = 12 yrs is Rico's present age and we know m = r + 4 m = 12 + 4 m = 16 yrs is Mary's present age : b) determine if answer is correct by checking that it satisfies the conditions of the problem Check solution in the statement: " Ten years ago Mary was 3 times as old as Rico was then. " 16 - 10 = 3(12 - 10) 6 = 3(2); confirms the solutions : : Did this help straighten things out for you?
 Unit_Conversion_Word_Problems/309544: Multistep word problems Word problems are more complicated with two or more unknown values. First, assign a variable to each unknown value. The word problem should then be translated into the appropriate number of mathematical equations, which can then be solved by substitution. Keep in mind that the number of mathematical equations needed is equal to the number of variables. Consider the following multistep word problem: The sum of the ages of a brother and sister is 25. If four times the brother's age is subtracted from three times the sister's age, the difference is 5.Consider just the first sentence of this multistep word problem. Sentence 1: The sum of the ages of a brother and sister is 25. Give an equation that represents this statement using as the age of the brother and as the age of the sister ??????If four times the brother's age is subtracted from three times the sister's age, the difference is 5.Give an equation that represents this statement using b as the age of the brother and s as the age of the sister. 1 solutions Answer 221443 by ankor@dixie-net.com(15652)   on 2010-05-29 12:35:00 (Show Source): You can put this solution on YOUR website!The sum of the ages of a brother and sister is 25. If four times the brother's age is subtracted from three times the sister's age, the difference is 5.Consider just the first sentence of this multi-step word problem. : Let b = brother's present age Let s = sister's present age : Sentence 1: The sum of the ages of a brother and sister is 25. Give an equation that represents this statement using as the age of the brother and as the age of the sister b + s = 25 : If four times the brother's age is subtracted from three times the sister's age, the difference is 5. Give an equation that represents this statement using b as the age of the brother and s as the age of the sister. 3s - 4b = 5 : Substitution is one way to solve this, rearrange the 1st equation to: b = (25-s) : Substitute (25-s) for b in the 2nd equation 3s - 4(25-s) = 5 3s - 100 + 4s = 5 3s + 4s = 5 + 100 7s = 105 s = s = 15 yrs is sister's age then using the equation b = 25-s: b = 25 - 15 b = 10 yrs is brothers age ; : Confirm the solution in the 2nd statement; "four times the brother's age is subtracted from three times the sister's age, the difference is 5." 3(15) - 4(10) = 5 : Do you understand this now???
 Numbers_Word_Problems/309617: find three positive numbers whose sum is 44 if the second number is twice the first and the third number is two thirds the first. 1 solutions Answer 221442 by ankor@dixie-net.com(15652)   on 2010-05-29 12:09:38 (Show Source): You can put this solution on YOUR website!find three positive numbers whose sum is 44 if the second number is twice the first and the third number is two thirds the first. : x + y + z = 44 : "the second number is twice the first" y = 2x : "the third number is two thirds the first." z = x : Replace y and z in the 1st equation, find x: x + 2x + x = 44 3x + x = 44 multiply both sides by 3, results: 9x + 2x = 3(44) 11x = 132 x = x = 12 then y = 2(12) y = 24 and z = (12) z = 8 : : Check solution: 12 + 24 + 8 = 44
 logarithm/309405: I'm new to logs and I'm not sure how to answer these questions: (any help would be greatly appreciated, thanks :D ) 1) log(base4) (x^2 - 3) + log(base 4) 10 = 1 2) log(base 5)3 - log(base 5) 5x = 2 3) ln (x+7) + ln (x+3) = ln 77 4) ln (x+2) - ln (x-1) = 1 1 solutions Answer 221387 by ankor@dixie-net.com(15652)   on 2010-05-28 20:32:32 (Show Source): You can put this solution on YOUR website!1) log(base4) (x^2 - 3) + log(base 4) 10 = 1 addition of logs is the same as multiply so we can write it: log4(10*(x^2-3)) = 1 log4(10x^2 - 30) = 1 Write the exponent equiv of logs 4^1 = 10x^2 - 30 4 = 10x^2 - 30 4 + 30 = 10x^2 34 = 10x^2 x^2 = 34/10 x^2 = 3.4 x = x = 1.844 : 2) log(base 5)3 - log(base 5) 5x = 2 subtracting logs is the same as divide so we can write it exponent equiv 5^2 = 25 = Multiply by 5x 25(5x) = 3 125x = 3 x = : : 3) ln (x+7) + ln (x+3) = ln 77 ln((x+7)*(x+3)) = ln(77) FOIL ln((x^2+10x+21) = ln(77) same as x^2 + 10x + 21 = 77 x^2 + 10x + 21 - 77 = 0 A quadratic equation x^2 + 10x - 56 = 0 Factors to (x-14)(x-4) = 0 only the positive solution can be used here x = 4 : 4) ln (x+2) - ln (x-1) = 1 find the e^ of both sides = 2.71828 x + 2 = 2.71828(x-1) x + 2 = 2.71828x - 2.71828 2.71828 + 2 = 2.71828x - x 4.71828 = 1.71828x x = 4.71828/1.71828 x = 2.746
 Human-and-algebraic-language/309519: My son who is in 4th grade needs help with this problem: Mr. Herman had \$125, and Mr. Chandra had \$80. After each of them had paid for a concert ticket, Mr. Herman had six times as much money as Mr. Chandra. How much money did Mr. Chandra have left? 1 solutions Answer 221374 by ankor@dixie-net.com(15652)   on 2010-05-28 18:58:00 (Show Source): You can put this solution on YOUR website!Mr. Herman had \$125, and Mr. Chandra had \$80. After each of them had paid for a concert ticket, Mr. Herman had six times as much money as Mr. Chandra. How much money did Mr. Chandra have left? : Let x = cost of the ticket 125 - x = 6(80-x) 125 - x = 480 - 6x -x + 6x = 480 - 125 5x = 355 x = x = \$71 is cost of ticket then 80 - 71 = \$9, Mr C had left : Check solution in the original equation 125 - 71 = 6(9)
 Surface-area/309443: The volume of an open box with a square base and rectangular sides us 250 cubed inches. if sides are double thickness and the bottom is triple thickness, what size box will use the least amount of material?1 solutions Answer 221371 by ankor@dixie-net.com(15652)   on 2010-05-28 18:35:50 (Show Source): You can put this solution on YOUR website!The volume of an open box with a square base and rectangular sides us 250 cubed inches. if sides are double thickness and the bottom is triple thickness, what size box will use the least amount of material? : Surface area of an open box with a square base x = side of the square base h = height of the box S.A = x^2 + 4(x*h) : Surface area required with a triple thickness bottom and double thickness sides S.A. = 3x^2 + 8(x*h) : Vol = x^2*h x^2*h = 250 h = : S.A = 3x^2 + 8(x*h) Substitute for h S.A. = 3x^2 + 8(x*) S.A. = 3x^2 + 8() S.A. = 3x^2 + : Plot this equation You can see min material for surface area occurs when x = 7 Find the height h = h = 5.1 inches : Least amt of material used in a 7 by 7 by 5.1 inch box : :
 Rate-of-work-word-problems/309458: a,b, andc can finish a job in 6 days. if b and c work together, the job will take 9 days;if a and c work together, the job will be done in 8 days. in how many days can each man working alone do the job? 1 solutions Answer 221332 by ankor@dixie-net.com(15652)   on 2010-05-28 16:19:54 (Show Source): You can put this solution on YOUR website!a, b, and c can finish a job in 6 days. if b and c work together, the job will take 9 days; if a and c work together, the job will be done in 8 days. in how many days can each man working alone do the job? : Let the completed job = 1 : "a, b, and c can finish a job in 6 days." 1. + + = 1 : "if b and c work together, the job will take 9 days;" 2. + = 1 : "if a and c work together, the job will be done in 8 days." 3. + = 1 : Multiply eq1 by 3, and eq2 by 2 + + = 3 + + = 2 --------------------------subtraction eliminates a & b, find c 18/a = 1 Mult both sides by a a = 18 hrs alone : replace a with 18 in eq3, find c + = 1 Multiply by 18c 8c + 18(8) = 18c 8c + 144 = 18c 144 = 18c - 8c 144 = 10c c = c = 14.4 hrs alone : replace c with 14.4 in eq2, find b + = 1 multiply by 14.4b 14.4(9) + 9b = 14.4b 129.6 = 14.4b - 9b 129.6 = 5.4b b = b = 24 hrs alone : solution: a=18 hrs, b=24 hrs, c= 14.4 hrs : See if that flies in the eq1 + + .333 + .25 + .417 = 1
 Travel_Word_Problems/309461: a person traveling 4 hr by plane and 25 hr by ship covers 1580 miles. if the speed of the plane had been one-half of the actual speed and the speed of the ship had been one-forth greater, the person would have traveled only 1315 miles in the same length of time. find the speeds of both the plane and the ship.1 solutions Answer 221316 by ankor@dixie-net.com(15652)   on 2010-05-28 15:29:54 (Show Source): You can put this solution on YOUR website!A person traveling 4 hr by plane and 25 hr by ship covers 1580 miles. If the speed of the plane had been one-half of the actual speed and the speed of the ship had been one-forth greater, the person would have traveled only 1315 miles in the same length of time. Find the speeds of the plane and the ship. : Let x = speed of plane and Let y = speed of shipe : Two distance equations; dist = time * speed : 4x + 25y = 1580 and 4(.5x) + 25(1.25y) = 1315 2x + 31.25y = 1315 : Multiply above equation by 2. Subtract the first equation 4x + 62.5y = 2630 4x + 25y = 1580 ---------------------subtraction eliminates x, find y: 37.5y = 1050 y = y = 28 mph speed of the ship : Find x using the 1st equation 4x + 25(28) = 1580 4x + 700 = 1580 4x = 1580 - 700 4x = 880 x = x = 220 mph speed of the plane : : Check solution in 2nd equation where plane speed = 110 and boat speed = 35: 4(110) + 25(35) = 440 + 875 = 1315
 Surface-area/309326: A farmer has a square plot of land. An irrigation system can be installed with the option of one large circular sprinkler, or nine small sprinklers. The farmer wants to know which plan will provide water to the greatest percentage of land in the field, regardless of the cost and the watering pattern.”1 solutions Answer 221314 by ankor@dixie-net.com(15652)   on 2010-05-28 15:19:31 (Show Source): You can put this solution on YOUR website!A farmer has a square plot of land. An irrigation system can be installed with the option of one large circular sprinkler, or nine small sprinklers. The farmer wants to know which plan will provide water to the greatest percentage of land in the field, regardless of the cost and the watering pattern.” : We can use an example. Assume a square field 90' on a side : then diameter of circular area will be 90' also. r = 45 A = A = 6362 sq/ft : Using 9 circular sprinklers, each would have a diameter of 30'. r = 15 A = A = 6362 sq/ft Also!!
 Square-cubic-other-roots/309426: Can you help me with this word problem? Landing speed and weight. Because the gross weight of the Piper Cheyenne depends on how much fuel and cargo are on board, the proper landing speed is not always the same. The formula V =√1.496L gives the landing speed in terms of the gross weight only. a) Find the landing speed if the gross weight is 7000 lb. b) What gross weight corresponds to a landing speed of 115 ft/sec? 1 solutions Answer 221312 by ankor@dixie-net.com(15652)   on 2010-05-28 14:49:37 (Show Source): You can put this solution on YOUR website!Landing speed and weight. Because the gross weight of the Piper Cheyenne depends on how much fuel and cargo are on board, the proper landing speed is not always the same. : The formula V = gives the landing speed in terms of the gross weight only. : a) Find the landing speed if the gross weight is 7000 lb. replace L with 7000 V = : V = V = 102.33 ft/sec : b) What gross weight corresponds to a landing speed of 115 ft/sec? = 115 Square both sides 1.496L = 13225 L = L = 8,840.24 lb gross weight
 Miscellaneous_Word_Problems/309433: I think I got the equation right to solve this word problem: You drive to California. On the way, you averaged 10 miles per hour less, and the drive took you 5 extra hours. What was your average speed on thw\e way to California? This is the formula I used but not sure how to solve it: 1500=(R-10)(T+5)1 solutions Answer 221308 by ankor@dixie-net.com(15652)   on 2010-05-28 14:23:38 (Show Source): You can put this solution on YOUR website! You drive to California. On the way, you averaged 10 miles per hour less, and the drive took you 5 extra hours. What was your average speed on thw\e way to California? : I would do it this way: : Let r = speed on the way to Calif then (r+10) = speed on the return trip : Let 1500 mi = one way distance : Write a time equation; time = dist/speed to Calif time - return time = 5 hrs - = 5 hrs : multiply by r(r+10), results: 1500(r+10) - 1500r = 5r(r+10) 1500r + 15000 - 1500r = 5r^2 + 50r : Combine on the right 0 = 5r^2 + 50r - 15000 : simplify, divide by 5, results r^2 + 10r - 3000 = 0 : Factors to (r+60)(r-50) = 0 : the positive solution is what we want here r = 50 mph is the speed to Calif : : Check solutions by finding the times: (return trip speed = 60 mph) 1500/50 = 30 hrs 1500/60 = 25 hrs ---------------- time dif: 5 hrs
 Travel_Word_Problems/309424: A plane averaged 158 km/h. On the returned trip the plane only averaged 112 km/h. While flying back into the same wind, find the speed of the wind and of the plane in still air.1 solutions Answer 221305 by ankor@dixie-net.com(15652)   on 2010-05-28 13:58:21 (Show Source): You can put this solution on YOUR website!A plane averaged 158 km/h. On the returned trip the plane only averaged 112 km/h. While flying back into the same wind, find the speed of the wind and of the plane in still air. : Let s = speed of the plane in still air Let w = speed of the wind From the given information we can write two equation s + w = 158 s - w = 112 -------------Addition eliminates w, find s 2s = 270 s = 135 km/hr in still air Find w 135 + w = 158 w = 158 - 135 w = 23 km/hr is the wind : Check in "against the wind" equation 135 - 23 = 112
 Travel_Word_Problems/309272: You drive 220 miles to see a friend. The return trip takes 20 minutes less than the original trip, and your average speed is 5 miles per hour faster. What is your average speed on the return trip?1 solutions Answer 221180 by ankor@dixie-net.com(15652)   on 2010-05-27 22:00:38 (Show Source): You can put this solution on YOUR website!You drive 220 miles to see a friend. The return trip takes 20 minutes less than the original trip, and your average speed is 5 miles per hour faster. What is your average speed on the return trip? : Let s = return trip speed then (s-5) = original trip speed : Change 20 min to 1/3 hr : Write a time equation, Time = dist/speed Original trip time - return trip time = 1/3 hr - = multiply equation by 3s(s-5) results: 3s(220) - 3(s-5)*220 = s(s-5) 660s - 660(s - 5) = s^2 - 5s 660s - 660s + 3300 = s^2 - 5s 0 = s^2 - 5s - 3300 Factors to (s-60)(s+55) = 0 s = +60 mph
 Polynomials-and-rational-expressions/308985: Simplify if possible 1 solutions Answer 221068 by ankor@dixie-net.com(15652)   on 2010-05-27 16:43:42 (Show Source): You can put this solution on YOUR website! Factor the denominators Over the common denominator = =
 Volume/309025: find the total number of bowling balls with a radius of 3.25" that can fit on the four shelves. The shelving unit is 30" long, 8" wide and 24" high. the bottom shelf is 3" high and the other three are 6" high. Please help! thanks1 solutions Answer 221065 by ankor@dixie-net.com(15652)   on 2010-05-27 16:09:24 (Show Source): You can put this solution on YOUR website!find the total number of bowling balls with a radius of 3.25" that can fit on the four shelves. The shelving unit is 30" long, 8" wide and 24" high. the bottom shelf is 3" high and the other three are 6" high. : A ball with a 3.25' radius has a diameter of 6.5" (height of the ball). That won't fit on any of the shelves. the answer is 0 balls
 Numeric_Fractions/309190: I don't know how to do this I really need help, someone pacient and friendly please! Thank-you.1 solutions Answer 221051 by ankor@dixie-net.com(15652)   on 2010-05-27 15:35:00 (Show Source): You can put this solution on YOUR website!Do what???
 Linear-equations/309034: I need help and real confused. Find the value of x ... f(x) = -1/2x +6 1 solutions Answer 221049 by ankor@dixie-net.com(15652)   on 2010-05-27 15:33:25 (Show Source): You can put this solution on YOUR website! f(x) = x + 6 Find x when f(x) = 0 x + 6 = 0 : x = -6 Multiply both sides by 2 x = -12
 Average/309108: A total of 50 juniors & seniors were given a math test. The 35 juniors attained an average score of 80 while the 15 seniors attained an average of 70. What was the average score for all 50 students that took the test? I dont understand how.. to get the answer1 solutions Answer 221048 by ankor@dixie-net.com(15652)   on 2010-05-27 15:27:39 (Show Source): You can put this solution on YOUR website!A total of 50 juniors & seniors were given a math test. The 35 juniors attained an average score of 80 while the 15 seniors attained an average of 70. What was the average score for all 50 students that took the test? : Av =
 Linear-equations/309180: Please help!! The answer is 19.. I just don't know how to get it. I keep getting 18 as an answer. A construction company spent 26 hours on two jobs. One job took 5 more the twice the number of hours of the other. How long did the larger job take? Thank you so much for your help!! Rebecca1 solutions Answer 221046 by ankor@dixie-net.com(15652)   on 2010-05-27 15:23:49 (Show Source): You can put this solution on YOUR website!A construction company spent 26 hours on two jobs. One job took 5 more the twice the number of hours of the other. How long did the larger job take? : Let x = time for larger job Let y = time for the other job : "A construction company spent 26 hours on two jobs." x + y = 26 y = (26-x); this form for substitution : "One job took 5 more the twice the number of hours of the other." x = 2y + 5 : How long did the larger job take? Replace y with (26-x) in the above equation x = 2(26-x) + 5 x = 52 - 2x + 5 x + 2x = 52 + 5 3x = 57 x = x = 19 hrs : : Check solution; y = 26-19 = 7 hrs "One job took 5 more the twice the number of hours of the other." 19 = 2(7) + 5
 Quadratic_Equations/308990: assume that you sell 65 sandwiches for \$1 each. if you lose 8 customers each time you raise the price \$.10 what is the price that will produce the greatest amount of sales? what is the amount of revenue that you will bring in? solve using quadratics1 solutions Answer 221027 by ankor@dixie-net.com(15652)   on 2010-05-27 13:46:33 (Show Source): You can put this solution on YOUR website!assume that you sell 65 sandwiches for \$1 each. if you lose 8 customers each time you raise the price \$.10 what is the price that will produce the greatest amount of sales? what is the amount of revenue that you will bring in? solve using quadratics : Let x = no. of .10 increases & no. of 8 customer decreases : Revenue = price * no. sold R(x) = (1 + .10x)(65 - 8x) FOIL R(x) = 65 - 8x + 6.5x - .8x^2 R(x) = 65 - 1.5x - .8x^2 A quadratic equation y = -.8x^2 - 1.5x + 65 Find the axis of symmetry; x = -b/(2a), a=-.8, b=-1.5 x = x = x = -.9375; a negative value means any .10 increase makes you lose money
 Rational-functions/308975: Suppose that x and y vary inversely and that y=1/6 when x=3. Write a function that models the inverse variation and find y when x=10. a) ; b) ; c) ; d) ; 1 solutions Answer 221016 by ankor@dixie-net.com(15652)   on 2010-05-27 13:19:05 (Show Source): You can put this solution on YOUR website!Suppose that x and y vary inversely let k = the constant of variation y = : and that y=1/6 when x=3. = Cross mult and find k 3k = 6 k = k = 2 : Write a function that models the inverse variation y = : find y when x=10. y = y =
 Rational-functions/308977: Suppose that y varies jointly with w and x and inversely with z and y=360 when w=8, x=25, and z=5. Write the equation that models the relationship. Then find y when w=4 and z=3.1 solutions Answer 221012 by ankor@dixie-net.com(15652)   on 2010-05-27 12:57:51 (Show Source): You can put this solution on YOUR website!Suppose that y varies jointly with w and x and inversely with z Let k = the variation constant y = : and y=360 when w=8, x=25, and z=5. Write the equation that models the relationship. = 360 : = 360 : 40x = 360 k = k = 9 is the constant and y = is the equation : Then find y when w=4 and z=3. We have to know x, when you know that, use the above equation to find y
 Equations/309012: I need to find all real or imaginary solutions to this equation. Use the method of your choice. √7x+29 = x + 3 note: sqrt extends over 7x+29 1 solutions Answer 220964 by ankor@dixie-net.com(15652)   on 2010-05-27 08:05:44 (Show Source): You can put this solution on YOUR website!Use the method of your choice. = x + 3 Square both sides 7x + 29 = (x + 3)^2 FOIL the right sides 7x + 29 = x^2 + 6x + 9 Combine like terms on the right 0 = x^2 + 6x - 7x + 9 - 29 A quadratic equation x^2 - x - 20 = 0 Factors to (x-5)(x+4) = 0 two solutions x = +5 x = -4 ; check both solution in original equation x = 5 = 5 + 3 = 5 + 3 = 8 8 = 8, a good solution : x=-4 = -4 + 3 = -4 + 3 = -1 +1 does not = -1, not a good solution