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 Travel_Word_Problems/676270: Jim leaves 25 miles from work. He rides his bike at 9mph to the metro which travels at 30mph. He spends 2 minutes less on his bike than on the metro. What's the distance from his house to the metro? The answer is five miles. However, here is how I set it up. 9(x-2) + 30x = 25 and then I tried 9(x-.03) + 30x = 25. Not once did I get the answer. I'm stuck.1 solutions Answer 420295 by ankor@dixie-net.com(15746)   on 2012-11-05 19:00:27 (Show Source): You can put this solution on YOUR website! Jim leaves 25 miles from work. He rides his bike at 9mph to the metro which travels at 30mph. He spends 2 minutes less on his bike than on the metro. What's the distance from his house to the metro? : I don't get that answer either, but because we are using mph, you have to convert two minutes to hrs. : let = time to bike to the metro at 9 mph Change two min to hrs: 2/60 = 1/30 hr then (t+) = time on the metro at 30 mph : WRite a diat equation; dist = speed * time : bike dist + metro dist = 25 mi 9t + 30(t+) = 25 9t + 30t + 1 = 25; (30's cancel) 39t = 25 - 1 39t = 24 t = 24/39 = 8/13 hrs on the bike Find the dist 9* = 5.54 miles to the metro : : Check this by finding the distance on the metro [+] * 30 = .6487 * 30 = 19.46 mi on the bus : Find the total distances of bike and bus 5.54 + 19.46 = 25 mi, confirms our solution of 5.54 to the metro
 Travel_Word_Problems/676243: a boat traveled 72 miles downstream and back. The trip downstream took 3 hours. The trip back took 18 hours. Find the speed of the boat in still water and the speed of the current.1 solutions Answer 420263 by ankor@dixie-net.com(15746)   on 2012-11-05 16:30:02 (Show Source): You can put this solution on YOUR website! a boat traveled 72 miles downstream and back. The trip downstream took 3 hours. The trip back took 18 hours. Find the speed of the boat in still water and the speed of the current. : Let s = boat speed in still water let c = speed of the current Then (s+c) = effective speed downstream and (s-c) = effective speed upstream : Write a distance equation for each way; dist = time * speed : 3(s+c) = 72 18(s-c) = 72 Simplify both equations, divide the 1st by 3 and the 2nd by 18 and you have s + c = 24 s - c = 4 ------------- adding equations eliminates c, find s 2s = 28 s = 28/2 s = 14 mph, boat speed in still water : I'll let you find the speed of the current Check your solution in the original equations
 Geometry_Word_Problems/675817: A Norman Window is a rectangle with a semi-circle on top of it. Big Sky Window is designing a Norman window that will require 8m of trim around the perimeter of the window. What dimensions will allow the maximum amount of light to enter a house?1 solutions Answer 420223 by ankor@dixie-net.com(15746)   on 2012-11-05 14:55:16 (Show Source): You can put this solution on YOUR website!A Norman Window is a rectangle with a semi-circle on top of it. Big Sky Window is designing a Norman window that will require 8m of trim around the perimeter of the window. What dimensions will allow the maximum amount of light to enter a house? : This can be summed up in the statement: "Find the max area for a perimeter of 8 meters" : Let W = the width of the rectangular portion and the diameter of semi-circle .5W = the radius of the semicircle let L = the length of the rectangular portion (height of the window) : Perimeter 2 vert lengths + 1 lower width + half the circumference 2L + W + .5W*pi = 8 2L + W + 1.57W = 8 2L + 2.57W = 8 Divide by 2 L + 1.285W = 4 L = (4-1.285W) : Area A = L*W + [.5*pi*(.5W)^2] A = L*W + [.5*pi*.25W^2 A = L*W + .3927W^2 Replace L with (4-1.285W) A = W(4-1.285W) + .3927W^2 A = 4W-1.285W^2 + .3927W^2 A quadratic equation A = -.8923W^2 + 4W Find the axis of symmetry W = -4/2(-.8923) W = -4/-1.7846 W = 2.24 meters is the width of the window for max area Find L L = 4 - 1.285(2.24) L = 4 - 2.8784 L = 1.12 meters is the height of the window for max area : : : Check this by finding the perimeter p = 2(1.12 + 2.24 +(.5*pi*2.24) p = 2.24 + 2.24 + 3.52 p = 8 meters
 Matrices-and-determiminant/675900: I Missed A Day At School And My Teacher Is Not Able To Teach Me This At All, So Im Stuck. I Have The Problem 3x-y=1 2x=4y=3 And The Directions Say "Write The Matrix You Would Use To Solve The Following Systems, Then Using Your Calculator (Which I Dont Have), Find The Solution To Each System. I Literally Dont Understand This At All! 1 solutions Answer 420136 by ankor@dixie-net.com(15746)   on 2012-11-04 21:32:10 (Show Source): You can put this solution on YOUR website!3x - y = 1 2x + 4y = 3 : this would be a 2 by 3 matrix 3 -1 1 2 4 3 : the matrix value are made up of the coefficients of x and y and the number : In your calc set the size of the matrix(2 by 3) then enter each value just as it is above. Follow the rules of your calc to solve : This came out [A] [(3 -1 1] (2 4 3)} and the solution rref([A]) [(1 0 .5); means x = .5 [0 1 .5); means y = .5 : Of course you could solve this using elimination of substitution too
 Numbers_Word_Problems/675925: Chris collected toys for charity she donated 3/4 to charity a and 1/3 of remaining toys to charity b. after the 2 donations, she had 10 toys left How many toys did she originally collect. I know the answer is 60 but cannot figure how to get to the answer. HELP Please1 solutions Answer 420132 by ankor@dixie-net.com(15746)   on 2012-11-04 21:17:34 (Show Source): You can put this solution on YOUR website!Chris collected toys for charity she donated 3/4 to charity a and 1/3 of remaining toys to charity b. after the 2 donations, she had 10 toys left How many toys did she originally collect. : t = original number of toys The equation (note that when he gave away 3/4, he has 1/4 left) t = t + [*t] + 10 t = t + t + 10 multiply by 12 and cancel the denominators 12t = 3(3t) + 1t + 12(10) 12t = 9t + t + 120 you can complete this, now I know
 Miscellaneous_Word_Problems/675886: Find two different numbers for the values of x and y that will make x to the yth power and y to the xth power equal.1 solutions Answer 420128 by ankor@dixie-net.com(15746)   on 2012-11-04 21:05:53 (Show Source): You can put this solution on YOUR website!Find two different numbers for the values of x and y that will make x to the yth power and y to the xth power equal. : How about x = 2 y = 4
 Average/675698: The formula for the time that a certain traffic light remains yellow is t=1/8s+1, where t represents the time in seconds and s represents the speed limit in miles per hour. If the light is yellow for 6 seconds, what is the speed limit in miles per hour? I tried 6=1/8s+1 and I did the reciprocal, but that confuses me. Do i subtract 1 first or do i multiply the 8?1 solutions Answer 420105 by ankor@dixie-net.com(15746)   on 2012-11-04 19:53:20 (Show Source): You can put this solution on YOUR website!The formula for the time that a certain traffic light remains yellow is t=1/8s+1, where t represents the time in seconds and s represents the speed limit in miles per hour. If the light is yellow for 6 seconds, what is the speed limit in miles per hour? : Assume the formulas is: s + 1 = t t = 6 sec s + 1 = 6 s = 6 - 1 s = 5 multiply both sides by 8 s = 8(5) s = 40 mph
 Age_Word_Problems/675805: A man spent 1/3 of his life in England, 1/4 of it in Scotland and the remainder of it, which is 40 years, in Canada. What was his age?1 solutions Answer 420095 by ankor@dixie-net.com(15746)   on 2012-11-04 18:59:08 (Show Source): You can put this solution on YOUR website!A man spent 1/3 of his life in England, 1/4 of it in Scotland and the remainder of it, which is 40 years, in Canada. What was his age? : Let a = his age : a = a + a + 40 mult by 12 to get rid of the denominators, results: 12a = 4a + 3a + 12(40) 12a = 7a + 480 12a - 7a = 480 5a = 480 a = 480/5 a = 96 is his age : Check this: *96 + *96 + 40 = 32 + 24 + 40 = 96
 Functions/675840: What is the answer for: f/-3 + 5= 8 ? My son and I are saying we are both right but its impossible. The answer I came up with is -9. Is this correct? My son came up with -1.1 solutions Answer 420094 by ankor@dixie-net.com(15746)   on 2012-11-04 18:49:30 (Show Source): You can put this solution on YOUR website!Assuming the problem is: + 5 = 8 : = 8 - 5 : = 3 : Multiply both sides by -3 f = 3 * -3 f = -9 : You can check this: replace f with -9 + 6 = 8 +3 + 5 = 8
 Polynomials-and-rational-expressions/675620: re-post I made an ERROR Sailboat speed. The sail area-displacement ratio S provides a measure of the sail power available to drive a boat. For a boat with a displacement of d pounds and a sail area of A square feet S is determined by the function. The given formula A=16Ad^-2/3 a. Find S to the nearest tenth for the Tartan 4100, which has a sail area of 810 square feet and a displacement of 23,245 pounds. b. Write d in terms of A and S1 solutions Answer 420088 by ankor@dixie-net.com(15746)   on 2012-11-04 18:19:43 (Show Source): You can put this solution on YOUR website!Sailboat speed. The sail area-displacement ratio S provides a measure of the sail power available to drive a boat. For a boat with a displacement of d pounds and a sail area of A square feet S is determined by the function. The given formula S=16Ad^-2/3, (think it should be S=) : a. Find S to the nearest tenth for the Tartan 4100, which has a sail area of 810 square feet and a displacement of 23,245 pounds. S = 16*810*23245^(-2/3) Using a calc S = 12960*.0012277604 S = 15.9 knots : b. Write d in terms of A and S 16*A*d^(-2/3) = S d^(-2/3) = Raise both sides to (-3/2) to give d an exponent of 1 d =
 Human-and-algebraic-language/675390: a rectangular photo is surrounded by a grey border that makes up the picture frame. The total area of the picture frame is the expression ( 4ab + 6a + 10b + 15) cm^2. The the width between the actual photo and the frame has a distance of b and the length between the actual photo and the frame has a distance of a . What are the dimensions of the photo?1 solutions Answer 419925 by ankor@dixie-net.com(15746)   on 2012-11-03 21:39:13 (Show Source): You can put this solution on YOUR website!a rectangular photo is surrounded by a grey border that makes up the picture frame. The total area of the picture frame is the expression ( 4ab + 6a + 10b + 15) cm^2. The the width between the actual photo and the frame has a distance of b and the length between the actual photo and the frame has a distance of a . What are the dimensions of the photo? : Draw this out: the 4 corners are 4ab, leaving 2 each frame areas of 3a and 2 each of 5b, The picture is 3 by 5 (an area of 15)
 Linear_Equations_And_Systems_Word_Problems/674810: HI MY NAME IS TIAWANA AND I NEED HELP SOLVING MY HOMEWORK PROBLEMS. DETERMINE IF THE GIVEN ORDERED PAIR IS A SOLUTION TO THE SYSTEM OF EQUATIONS. (5/4,3) 12X-4=22-Y MY WORK I'VE DONE: 12(5/4)+4=22-3 ?=19 I'M HAVING TROUBLE AT THE QUESTION MARK THANKS1 solutions Answer 419918 by ankor@dixie-net.com(15746)   on 2012-11-03 21:11:08 (Show Source): You can put this solution on YOUR website!DETERMINE IF THE GIVEN ORDERED PAIR IS A SOLUTION TO THE SYSTEM OF EQUATIONS. (5/4,3) 12X-4=22-Y : You about got it: 12* = 15 (cancel 4 into 12, mult 5 by 3) then you have 15-4 = 22-3 11 does not = 19, so the ordered pair is NOT a solution
 Age_Word_Problems/675454: Need help solving this question. Maria is twice he age of Jonas, who is twice the age of Franklin. Franklin is 2yr less than half Maria's age.How old are Maria, Jonas, and Franklin?1 solutions Answer 419848 by ankor@dixie-net.com(15746)   on 2012-11-03 16:14:57 (Show Source): You can put this solution on YOUR website!Write an equation for each statement : "Maria is twice he age of Jonas," m = 2j : " who is twice the age of Franklin. j = 2f : "Franklin is 2yr less than half Maria's age." f = .5m - 2 : we know m = 2j and j = 2f, therefore m = 4f replace m with 4f f = .5(4f) - 2 f = 2f - 2 2 = 2f - f f = 2 yrs is Franklin's ager then m = 4(2) m = 8 yrs is Marie's age and j = 2(2) j = 4 yrs is Jona's age
 Quadratic_Equations/675395: A football initially on the ground is kicked in the air and follows a parabolic path after 2 seconds the football is 6 meters off the ground it reaches a maximum height of 8 meters after 4 seconds . Find the height of the football 7 seconds after the ball is kicked?1 solutions Answer 419846 by ankor@dixie-net.com(15746)   on 2012-11-03 16:03:21 (Show Source): You can put this solution on YOUR website!A football initially on the ground is kicked in the air and follows a parabolic path after 2 seconds the football is 6 meters off the ground it reaches a maximum height of 8 meters after 4 seconds. Find the height of the football 7 seconds after the ball is kicked? : Using the form y = ax^2 + bx + c, where, y is the height in meters, x = time in seconds, the ball starts at ground level therefore c = 0 : Two ordered pairs to find a, and b x=2; y=6 4a + 2b = 6 and x=4, y=8 16a + 4b = 8 : Use elimination, multiply the 1st equation by 2, subtract from the 2nd equation 16a + 4b = 8 8a + 4b = 12 ----------------subtraction eliminates b, find a 8a = -4 a = -4/8 a = -.5 : Find b using the 1st original equation 4(-.5) + 2b = 6 -2 + 2b = 6 2b = 6 + 2 b = 8/2 b = 4 : The equation: y = -.5x^2 + 4x Find the height when x = 7 y = -.5(7^2) + 4(7) y = -24.5 + 28 y = 3.5 meters after 7 seconds : Graphically
 logarithm/675254: Using the common or natural log to solve the exponnential equation symboliccally. 2^(8+4x)=1/16 Can you help me figure out this problem? I have tried to get help from a tutor. We worked it out together and we both came up with the same thing that was not an answer choice. I sure would appreciate your help.1 solutions Answer 419668 by ankor@dixie-net.com(15746)   on 2012-11-02 20:26:08 (Show Source): You can put this solution on YOUR website! 2^(8+4x) = 1/16 : Actually so we have an equiv equation of: It the bases are equal, the exponents are equal, so we have: 8 + 4x = -4 4x = -4 - 8 4x = -12 x = -12/4 x = -3 : : Check this in your calc: enter 2^(8+4(-3)) results: .0625 which is 1/16
 Travel_Word_Problems/674961: Two cyclists rode their bicycles up and down a hill. They averaged ten kilometer per hour on the way up and twenty kilometer per hour on the way down. What is their average speed for the entire trip?1 solutions Answer 419530 by ankor@dixie-net.com(15746)   on 2012-11-02 08:41:22 (Show Source): You can put this solution on YOUR website!Two cyclists rode their bicycles up and down a hill. They averaged ten kilometer per hour on the way up and twenty kilometer per hour on the way down. What is their average speed for the entire trip? : let d = the dist up (and the dist down) let a = average speed for the trip : Write a time equation, time = dist/speed : + = multiply by 20a to get rid of the denominators: 2ad + ad = 20(2d) 3ad = 40d divide both sides by d 3a = 40 a = 40/3 a = 13 km/hr for the entire trip
 Numbers_Word_Problems/674904: I am a four digit number. The number in my hundreds place is two less than the number in my ones. The number in my thousands place is odd. The number in my tens place is twice the number in my thousands and four more than the number in my ones. What number am I ?1 solutions Answer 419499 by ankor@dixie-net.com(15746)   on 2012-11-01 21:52:12 (Show Source): You can put this solution on YOUR website! I am a four digit number. a=1000 place b=100 c=10 d=ones : Write an equation for each statement: : The number in my hundreds place is two less than the number in my ones. b = d - 2 : The number in my thousands place is odd. : The number in my tens place is twice the number in my thousands c = 2a c has to equal 2, or 6; when a = 1 or 3; try a = 3 and c = 6 : and four more than the number in my ones. c = d + 4 6 = d + 4 d = 2 then b = d - 2 b = 2 - 2 b = 0 : we now have 3 0 6 2, see if that checks out
 Volume/674884: The volume of an outdoor pool in the shape of a rectangular prism is given by the polynomial (2a^3 + 8a^2 - 34a - 120) cubic meters. The pool is half full . The dimensions of the length and width of the base are (a +5)meters and (a-4)meters. What is the height of the water in the pool in meters1 solutions Answer 419461 by ankor@dixie-net.com(15746)   on 2012-11-01 20:22:20 (Show Source): You can put this solution on YOUR website! The volume of an outdoor pool in the shape of a rectangular prism is given by the polynomial (2a^3 + 8a^2 - 34a - 120) cubic meters. The pool is half full. The dimensions of the length and width of the base are (a +5)meters and (a-4)meters. What is the height of the water in the pool in meters : Use synthetic division : . . .__________________ -5 |2 + 8 - 34 - 120 : I came up with 2a^2 - 2a - 24 Factor this to:(a-4)(2a+6) : we know the width = (a-4), therefore the height of the pool = (2a+6) : but they want the height of the water, half the height of the pool: h = h = (a+3) is the height of the water
 Word_Problems_With_Coins/674803: Dan has nickels, dimes and quarters. He has a total of 33.60. He has four times as many quarters as dimes and one-half as many dimes as nickels. How many of each coin does he have? I put x nickels, y dimes, and z quarters. 5x + 10y + 25z = 3360. Next, I put z = y + 4 to represent "four times as many quarters as dimes." Next, I put either x = 1/2y or x = 0.5y to represent "one-half as many dimes as nickels. Next, I saw how 1/2y or 0.5y is really 1/2 times 10 or 0.5 times ten which equals five (5). Then I substituted for 5x + 10y + 25z = 3360 by plugging in the numbers as follows: 5(5) + 10y + 25(y+4) = 3360. When I solved it, it wasn't correct. I'm supposed to get 112 quarters, 28 dimes, and 56 nickels. Am I missing a step where I should write x + y + z? - And then substitute one at at time? This is different in that I may not be writing something correctly because this problem contains no amount but only the value as the total and that it contains 1/2 which I may be figuring wrong. Thanks in advance.1 solutions Answer 419446 by ankor@dixie-net.com(15746)   on 2012-11-01 19:42:40 (Show Source): You can put this solution on YOUR website! Dan has nickels, dimes and quarters. : Write an equation for each statement, get n and q in terms of d: : He has a total of 33.60. .05n + .10d + .25q = 33.60 5n + 10d + 25q = 3360, get rid of the decimals : He has four times as many quarters as dimes q = 4d : and one-half as many dimes as nickels. n = 2d : Replace n with 2d, replace q with 4d 5(2d) + 10d + 25(4d) = 3360 10d + 10d + 100d = 3360 120d = 3360 d = 3360/120 d = 28 dimes : See if you can find n and q, and check it in the 1st equation
 logarithm/674831: I am coming up with an answer but its from plugging it in a calculator, how do I work this backwards? I am coming up with x=1.82 Approximate answer: 3*5^(2-x)=41 solutions Answer 419444 by ankor@dixie-net.com(15746)   on 2012-11-01 19:30:09 (Show Source): You can put this solution on YOUR website!3*5^(2-x)=4 ; divide both sides by 3 5^(2-x) = 4/3 : using logs log(5^(2-x)) = log(4/3) : log equiv of exponents (2-x)*log(5) = log(4/3) .69897(2-x) = .1249 2 - x = 2 - x = .1787 2 - .1787 = x 1.82 = x
 Travel_Word_Problems/674689: Two boys, Shawn and Curtis, went for a walk. Shawn began walking 20 seconds earlier than Curtis. Shawn walked at a speed of 5 feet per second. Curtis walked at a speed of 6 feet per second. For how many seconds had Shawn been walking at the moment when the two boys had walked exactly the same distance?1 solutions Answer 419442 by ankor@dixie-net.com(15746)   on 2012-11-01 19:19:48 (Show Source): You can put this solution on YOUR website!Two boys, Shawn and Curtis, went for a walk. Shawn began walking 20 seconds earlier than Curtis. Shawn walked at a speed of 5 feet per second. Curtis walked at a speed of 6 feet per second. For how many seconds had Shawn been walking at the moment when the two boys had walked exactly the same distance? : let t = walking time of S then (t-20) = walking time of C; (started 20 sec after S) : Write a distance equation; dist = speed * time : 5t = 6(t-20) 5t = 6t - 120 120 = 6t - 5t t = 120 seconds, is S's walking time : : Check this by finding the distance each walked, should be equal C's walking time = 100 sec 5(120) = 600 ft 6(100) = 600 ft
 Miscellaneous_Word_Problems/674440: if x+y=4, What is the perimeter of a square with side length 2x^2+4xy+2y^2?1 solutions Answer 419441 by ankor@dixie-net.com(15746)   on 2012-11-01 18:46:24 (Show Source): You can put this solution on YOUR website!if x+y=4, What is the perimeter of a square with side length 2x^2+4xy+2y^2 : 2x^2 + 4xy + 2y^2 Factor 2(x^2 + 2xy + y^2) Factor 2(x+y)(x+y) Given that x + y = 4 2(4)(4) = 32, the side lengh then 4(32) = 128 is the perimeter of the square
 Trigonometry-basics/674425: The minute hand of a clock is 4 inches long. How far does the tip of the minute hand move in 45 minutes? 1 solutions Answer 419413 by ankor@dixie-net.com(15746)   on 2012-11-01 16:56:50 (Show Source): You can put this solution on YOUR website!The minute hand of a clock is 4 inches long. How far does the tip of the minute hand move in 45 minutes? : A minute hand travels 360 degrees in 60 min, therefore : Find the circumference of a circle with a radius of 4 inches Multiply by 3/4 of an hr * = 18.85 inches
 Travel_Word_Problems/674408: a car traveling at 138km h how much distance in meters would it cover in 3 seconds?1 solutions Answer 419410 by ankor@dixie-net.com(15746)   on 2012-11-01 16:48:44 (Show Source): You can put this solution on YOUR website!a car traveling at 138km h how much distance in meters would it cover in 3 seconds? : Find how many meters in one seconds, mult by 3 * 3 = 115 meters in 3 sec
 Angles/674571: Please show me a 110 to 135 degree angle. It is the correct position to sit in to take pressure off one's back when one is experiencing sciatica pain? Thank you1 solutions Answer 419394 by ankor@dixie-net.com(15746)   on 2012-11-01 15:53:16 (Show Source): You can put this solution on YOUR website! The larger angle formed by the horizontal line at x=8 and to the right of the slanted line is 135 degrees : An angle of 110 degree angle is much steeper : Perhaps between these two extremes will be what you want
 Human-and-algebraic-language/674598: I have two problems I need help with! Thanks 1. The absolute value of a number is the same as the product of five and a number. Please translate for me... 2. The product of two consecutive integers is three more than the later integer. :)1 solutions Answer 419368 by ankor@dixie-net.com(15746)   on 2012-11-01 13:35:06 (Show Source): You can put this solution on YOUR website!1. The absolute value of a number is the same as the product of five and a number. Please translate for me... Makes no sense but the equation for the statement is: |x| = 5x : 2. The product of two consecutive integers is three more than the later integer. Let the two integers = x, (x+1) then x*(x+1) = (x+1) + 3 x^2 + x = x + 4 Combine like terms on the left, a quadratic equation; x^2 + x - x - 4 = 0 x^2 - 4 = 0 The difference of squares factor to: (x-2)(x+2 = 0 Two solutions x = 2 x = -2 Check both solutions in the original statement
 Quadratic_Equations/674561: Help please, Find the equation of the quadratic function whose graph runs through points (3,2),(4,3),(5,2)1 solutions Answer 419363 by ankor@dixie-net.com(15746)   on 2012-11-01 13:18:02 (Show Source): You can put this solution on YOUR website!Find the equation of the quadratic function y = ax^2 + bx+ c, whose graph runs through points (3,2),(4,3),(5,2) : Write a equation for each x,y pair, replacing x and y 3,2: 9a + 3b + c = 2 4,3: 16a + 4b + c = 3 5,2: 25a + 5b + c = 2 : Use elimination and substitution : Subtract the 1st equation from the 2nd 16a + 4b + c = 3 9a + 3b + c = 2 -----------------Subtraction eliminates c 7a + b = 1 b = (1-7a), for substitution : Subtract the 1st equation from the 3rd 25a + 5b + c = 2 9a + 3b + c = 2 -----------------Subtraction eliminates c 16a + 2b = 0 Replace b with (1-7a) 16a + 2(1-7a) = 0 16a + 2 - 14a = 0 2a = -2 a = -1 : Find b b = 1 - 7(-1) b = 1 + 7 b = 8 : Find c using the 1st original equation 9(-1) + 3(8) + c = 2 -9 + 24 + c = 2 15 + c = 2 c = 2 - 15 c = -13 : The equation, y = -x^2 + 8x - 13 : : YOu can confirm this, substitute for x and find y, for each given pair
 Reduction-of-unit-multipliers/674554: 45 centimeters is how many inches? I've entered in 17.7, 17.71, 17.72 into my homework checker and it keeps saying those answers are wrong. Any help would be very much appreciated! Thank you1 solutions Answer 419333 by ankor@dixie-net.com(15746)   on 2012-11-01 09:07:29 (Show Source): You can put this solution on YOUR website!The conversion factor for cm to inches. mult by .3937 .3937 * 45 = 17.7165
 Percentage-and-ratio-word-problems/674553: Is a 10% discount followed by a 20% discount equal to a 30% discount? Explain1 solutions Answer 419332 by ankor@dixie-net.com(15746)   on 2012-11-01 09:02:56 (Show Source): You can put this solution on YOUR website!Is a 10% discount followed by a 20% discount equal to a 30% discount? Explain NO After the first discount, that amt is discounted by the amt of 2nd discount : Take an example of an original price of \$100 discounted 10% after the 1st discount, the price is \$90 Now you discount \$90 by 20% .20 * 90 = 18 Now the price is 90 - 18 = \$72 : A straight 30% discount would give you a price of \$70
 Expressions-with-variables/674139: What is the difference between cubing and tripling a number?1 solutions Answer 419328 by ankor@dixie-net.com(15746)   on 2012-11-01 08:43:11 (Show Source): You can put this solution on YOUR website!Cubing n * n * n : Tripling 3 * n
 Linear_Algebra/674324: small theater has a seating capacity of 2000. When the ticket price is \$18, attendance is 1500. For each \$1 decrease in price, attendance increases by 100. (a) Write the revenue R of the theater as a function of ticket price x.1 solutions Answer 419259 by ankor@dixie-net.com(15746)   on 2012-10-31 21:52:35 (Show Source): You can put this solution on YOUR website! small theater has a seating capacity of 2000. When the ticket price is \$18, attendance is 1500. For each \$1 decrease in price, attendance increases by 100. (a) Write the revenue R of the theater as a function of ticket price x. : Let x = the \$1 ticket price change, also the number of 100 person increases : R(x) = (1500 + 100x)(18 - 1x) FOIL R(x) = 27000 + 1800x - 1500x - 100x^2 The equation R(x) = -100x^2 + 300x + 27000