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 absolute-value/119483: Assistance with a formula to find the average of 35%, 20%, 15%, 25%, and 5%. I am a transitional student, and need lots of help in this area. I thank you in advance for your assistance. Ms. Daphne Roach1 solutions Answer 87517 by Fombitz(13828)   on 2008-01-10 08:51:47 (Show Source): You can put this solution on YOUR website!To find an average, sum all of the points and divide by the number of points. Sum= 35+20+15+25+5=100 Number of points = 5 Average = Sum/Number =100/5=20 The average is 20%.
 Points-lines-and-rays/119341: This question is from textbook Geometry please help asap!!1 solutions Answer 87431 by Fombitz(13828)   on 2008-01-09 15:25:22 (Show Source): You can put this solution on YOUR website!You can solve two ways: That gives you a system of equations in r and s. The other, easier way is the equality of the angles. This way each equation only has one variable.
 Quadratic_Equations/119261: I solved the quadratic equation of 3x^2+11x-20=0 by factoring and have the correct answer of x=4/3, -5. How would I solve graphically by creating a tchart with 6 points that will lie on the parabola. Finding the vertex will be helpful. The graphical work must be sufficient to determine the solutions without knowing them from algebraic work. Any help you can give would be greatly appreciated.1 solutions Answer 87428 by Fombitz(13828)   on 2008-01-09 15:18:07 (Show Source): You can put this solution on YOUR website!Typically, I start at x=0 and move up by 1. 0 -20 1 -6 2 14 3 40 4 72 5 110 6 154 I see there is a zero between x=1 and x=2. Then go back the other direction. -1 -28 -2 -30 -3 -26 -4 -16 -5 0 The second zero is easy to find at x=-5. You can then go from x=1 to x=2 in increments of 0.1 to get more detail. 1.0 -6.0 1.1 -4.3 1.2 -2.5 1.3 -0.6 1.4 1.3 Now between x=1.3 and x=1.4. Again, keep getting finer and finer. 1.31 -0.4 1.32 -0.3 1.33 -0.1 1.34 0.1 Now between x=1.33 and x=1.34. You can keep going...
 Linear_Algebra/119186: 2/aČ-2a minus 3/aČ-a-21 solutions Answer 87425 by Fombitz(13828)   on 2008-01-09 14:55:54 (Show Source): You can put this solution on YOUR website! Whenever you subtract fractions, you need to have the same denominators. Let's look at each denominator first. So if you multiply the first denominator by (a+1) and then second denominator by (a), they will have a common denominator of a(a+1)(a-2). Remember whatever you multiply the denominator by, you also must multiply the numerator by. Remember this relation only makes sense when a does not equal 0,-1,or 2.
 Linear-systems/119333: I need to graph this equation: x+6=-5 it's supposed to be standard form like Ax+By=C My teacher said to use the numbers -2 -1 0 1 2 3 but they don't work.1 solutions Answer 87423 by Fombitz(13828)   on 2008-01-09 14:42:46 (Show Source): You can put this solution on YOUR website! If you subtract 6 from both sides, you get That is the standard form with A=1, B=0, and C=-11. So for any y value, x=-11.
 Probability-and-statistics/119330: If a die is tossed twice the probability of getting 3 on both tosses is?1 solutions Answer 87421 by Fombitz(13828)   on 2008-01-09 14:36:10 (Show Source): You can put this solution on YOUR website!First toss: P(3)=1/6. Second toss: P(3)=1/6. Since both events are independent, multiply the two probabilities. P(3, then 3) = 1/6*1/6=1/36
 Probability-and-statistics/119319: Each of the letters D E T E R M I N E D is written on a card. YOu mix the cards thoroughly. What is the probability of selecting an E, then an M? The first card is replaced before selecting the second card.1 solutions Answer 87406 by Fombitz(13828)   on 2008-01-09 14:00:52 (Show Source): You can put this solution on YOUR website!DETERMINED 2 D 3 E 1 T 1 R 1 M 1 I 1 N 10 letters total Probability of selecting an E is 3/10. Probability of selecting an M is 1/10. Since the events are independent and the first card is replaced, the probability of E then M is then the product of the two probabilities. P(E then M)=3/10*1/10=3/100.
 Triangles/119310: Which of the following could not be the lengths of the sides of a right triangle? A. 3, 4, 5 B. 5, 12, 13 C. 8, 15, 17 D. 12, 15, 18 E. 9, 12, 15 1 solutions Answer 87398 by Fombitz(13828)   on 2008-01-09 13:19:29 (Show Source): You can put this solution on YOUR website!Right triangles have sides that are Pythagorean triplets. That is, the following relationship holds true. where c is the hypotenuse and a and b are the other two sides. A.)3,4,5 9+16=25. 25=25. True B.)5,12,13 25+144=169. 169=169. True C.)8,15,17 64+225=289. 289=289. True D.)12,15,18 144+225=324. 369=324. False E.)9,12,15 81+144=225. 225=225. True D.) Cannot be a solution set since it doesn't uphold the Pythagorean theorem.
 Polynomials-and-rational-expressions/119314: 5/y+1 = 4/y+21 solutions Answer 87393 by Fombitz(13828)   on 2008-01-09 13:05:33 (Show Source): You can put this solution on YOUR website! Multiply both side by (y+1)(y+2) to get rid of denominators. Check the answer. The answer leads to a true statement. It's a good answer.
 Quadratic_Equations/119266: Evaluate the determinant |c2 a| |-a c| Please show all work Thank You1 solutions Answer 87378 by Fombitz(13828)   on 2008-01-09 10:31:17 (Show Source): You can put this solution on YOUR website!The determinant of a 2x2 matrix, A, given by, [A]= is given by In your case, [M]= I assume that's what you meant and not 2c. and then
 Quadratic_Equations/119298: Solve: 4(x-5)^2=-32 I got x=5=+- 2isqrt2 but I'm not sure if I am doing this correctly :)1 solutions Answer 87368 by Fombitz(13828)   on 2008-01-09 09:31:20 (Show Source): You can put this solution on YOUR website! is correct. You can always check your answer. True statement. Correct answer.
 Quadratic_Equations/119278: Solve the system of equations using matrices and identify the soluation 2x-3y+11z=10 -2x+2y-7z=6 Please show all work Thank You Q261 solutions Answer 87366 by Fombitz(13828)   on 2008-01-09 09:02:18 (Show Source): You can put this solution on YOUR website!You have 2 equations with 3 unknowns. That's not enough information to solve. Please re-post with the other equation.
 Money_Word_Problems/119284: The student council of Sta. Lucia High School needed \$2,250 for an annual trip. If five more members joined the group, each member would then save \$5. How many students planned to make the trip?1 solutions Answer 87365 by Fombitz(13828)   on 2008-01-09 08:59:00 (Show Source): You can put this solution on YOUR website!Let N be the number of students originally going. Let P be the per-person cost of the trip. N must be positive Originally 45 students planned to take the trip, costing \$50 each. Now 50 students are taking the trip, costing \$45 each or \$5 less.
 Numbers_Word_Problems/119286: The numerator is one less than the denominator. if 2 is subtracted from the numerator added to the denominator, the value of the fraction is 1/2. find the original fraction.1 solutions Answer 87364 by Fombitz(13828)   on 2008-01-09 07:51:43 (Show Source): You can put this solution on YOUR website!Let's call the fraction, "if 2 is subtracted from the numerator added to the denominator, the value of the fraction is 1/2" Multiply both sides by 2(A+2). Subtract A from both sides. Add 6 to both sides. Original fraction Check your answer True statement. Good answer.
 Travel_Word_Problems/119292: two planes leave at the same time. one flies west at 300km per hour. the other flies east at 450 km per hour. in how many hours will they be 2250 kilometers apart?1 solutions Answer 87363 by Fombitz(13828)   on 2008-01-09 07:45:27 (Show Source): You can put this solution on YOUR website!Distance(D) = Rate(R) x Time(t) Since one plane flies east and one plane flies west, add their distances together to find out how far apart they will be. Since they leave at the same time, t is the same for both, only R is different. In 3 hours, they will be 2250 km apart.
 Quadratic_Equations/119095: The equation V=12(1.25)^t describes the value (V) of a hockey card t years after purchase. a) What was the initial value of the hockey card? b) What was tha rate of appreciation expressed as a percentage? c) What will be the cards value 5 years after it was purchased? d) Use the graphing calculator to determine the number of years it would take for the card to be worth \$71.53. For (a) I got \$12 , for (b) I got 25% but I am not sure. Can someone please explain this to me. Thanks:)1 solutions Answer 87262 by Fombitz(13828)   on 2008-01-08 16:34:15 (Show Source): You can put this solution on YOUR website! a.) Yes, at time t=0 years, V=12 because (1.25)^t=(1.25)^0=1 b.) You can look at successive years to find the rate. At year 1, V=12(1.25)=15 Using time t=0 and time t=1, the rate of appreciation equals (new value minus old value) divided by old value As a percentage, 0.25 equals 25% c.)V[5]=12(1.25)^5=12(3.052)=\$36.62. d.) Looks like about 8 years. V[8]=12(1.25)^8=\$71.53.
 Probability-and-statistics/119143: I'm not sure if I choose the right type I am sorry if it is not. 27 people applied for a certain managerial job. According to one report, the first interview narrowed the field down to fewer than 7 candidates.Another report claimed that the first interview eliminated fewer than 23 applicants from consideration. If both reports are true, and if x applicants were eliminated by the first interview, what are the possible values of x? a)21 only b)22 only c)20 and 21 only d)21 and 22 only e)21,22, and 23 only I don't know what type of math to use to solve this problem. Thank you very much for your help, it is greatly appreciated.1 solutions Answer 87257 by Fombitz(13828)   on 2008-01-08 16:19:27 (Show Source): You can put this solution on YOUR website!First report "the first interview narrowed the field down to fewer than 7 candidates". We'll interpret that to mean exactly 6 or fewer candidates remain. Since the total number of candidates is 27, then the number of candidates eliminated was 21 or greater. Second report "eliminated fewer than 23 applicants from consideration" We'll interpret this to mean exactly 22 or fewer were eliminated. If both are true, then So both 21 and 22 meet the criteria. d)21 and 22 only
 Linear-systems/119112: 3x-3y+3z=-27 2x+2y+3z=-3 -3x+2y+2z=-31 solutions Answer 87234 by Fombitz(13828)   on 2008-01-08 14:47:07 (Show Source): You can put this solution on YOUR website!You didn't specify a solution method. Hopefully a matrix solution is OK. [A][x]=[b] where [A]= [x]= [b]= We then need to find the inverse of [A]([Ainv]) and matrix multiply by [b] to get [x]. [A][x]=[b] [x]=[Ainv][b] [Ainv]=(1/63)* [Ainv][b]=(1/63)* [x]= x=1 y=5 z=-5
 Linear_Equations_And_Systems_Word_Problems/119041: A local gym charges nonmembers \$10 per hour to use the tennis courts. Members pay a yearly fee of \$300 and 4\$ per hour for using the tennis courts. Write and solve an equation to find how many hours you must use the tennis courts to justify becoming a member.1 solutions Answer 87229 by Fombitz(13828)   on 2008-01-08 14:23:17 (Show Source): You can put this solution on YOUR website!You should get a membership when your costs as a non-member are greater than the costs would be for a member. Non-Member Costs > Member Costs Let H be the number of hours you rent the court. So, if you use more than 50 hours of court time, you should definitely get a membership.
 Linear-systems/119072: Write an equation of a line that contains the given point and is perpendicular to the given line. 2x+4y=-7; points(-3, -2)1 solutions Answer 87228 by Fombitz(13828)   on 2008-01-08 14:16:25 (Show Source): You can put this solution on YOUR website!The given line can be modified to the slope-intercept form. The given line has a slope, Perpendicular lines have slopes that are negative reciprocals of each other. The slope of the new line is then You can then use the point-slope form of a line. Check your answer using your point. True statement. Good answer.
 Polynomials-and-rational-expressions/119130: This question is from textbook Algebra Structure and Method Book 1 43 times 13 - 43 times 31 solutions Answer 87226 by Fombitz(13828)   on 2008-01-08 14:05:49 (Show Source): You can put this solution on YOUR website! Distributive property Simplify.
 Functions/118992: Find f^-1 of f(x)=x-3/x1 solutions Answer 87128 by Fombitz(13828)   on 2008-01-07 16:54:43 (Show Source): You can put this solution on YOUR website!Start with your function or To find the inverse, interchange y and x and solve for y. Original equation Interchange x and y
 Angles/118850: This question is from textbook discovering geometry an investigative approach show how three lines in a plane can intersect in no points,exactly one point ,exactly two points or exactly three points1 solutions Answer 87127 by Fombitz(13828)   on 2008-01-07 16:49:20 (Show Source): You can put this solution on YOUR website!No points, three parallel lines One point, three non-parallel lines Two points, two parallel lines plus one non-parallel Three points, three non-parallel lines