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# Recent problems solved by 'solver91311'

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 Divisibility_and_Prime_Numbers/372281: What is the prime factorization of 28 1 solutions Answer 265192 by solver91311(16877)   on 2010-11-16 19:52:45 (Show Source): You can put this solution on YOUR website! 28 is even, so divide by 2. Result, 14 and one factor of 2. 14 is even, so divide by 2. Result, 7 and a second factor of 2. 7 is prime. Prime factorization of 28 is 2 X 2 X 7. John My calculator said it, I believe it, that settles it
 Square-cubic-other-roots/372276: x to the power of 2 minus 200x plus 36001 solutions Answer 265190 by solver91311(16877)   on 2010-11-16 19:50:11 (Show Source): You can put this solution on YOUR website! What about it? Fascinating little quadratic trinomial. Was there a question somewhere, or were we just supposed to guess what it is you want? Next time you want to use this site, please read and follow the instructions for posting questions. They are pretty simple instructions and they are right there in front of your nose when you are posting. John My calculator said it, I believe it, that settles it
 Graphs/372268: so, i have question...we are learning about different types of graphs, mean, median, mode, range, interquartile range, upper quartile range, lower quartile range, and out liers. on of the questions is, DATA THAT IS MORE THAN 1, 5 TIMES THE INTERQUARTILE RANGE FROM THE QUARTILE. if you could help me with this vocabulary word it is one of the last ones and i cant find it. I already did 11 out of 14 and i would be so great full if you could help me. thank you so much, Ashley1 solutions Answer 265186 by solver91311(16877)   on 2010-11-16 19:44:30 (Show Source): You can put this solution on YOUR website! You didn't look very hard. I dropped your definition into Google and had the answer in about 3/4 of a second. Outliers are extreme values that are more than 1.5 times the interquartile range beyond the upper and lower quartiles John My calculator said it, I believe it, that settles it
 Average/372253: Find two points on the y-axis that are a distance of 5 units from (4,2).1 solutions Answer 265183 by solver91311(16877)   on 2010-11-16 19:37:26 (Show Source): You can put this solution on YOUR website! We know the two points are of the form and Using the distance formula: Where one of the points is , the other point is , and the distance is 5, we can write: Hence and Making the two points and John My calculator said it, I believe it, that settles it
 Functions/372260: Suppose that the functions g and h are defined for all real numbers x as follows. g(x)=x-4 h(x)=4x+2 Write the expression for (g-h)(x) and (g*h)(x) and evaluate (g+h)(-2) (g-h)(x)= (g*h)(x)= (g+h)(x)= 1 solutions Answer 265180 by solver91311(16877)   on 2010-11-16 19:27:48 (Show Source): You can put this solution on YOUR website! You get to simplify these yourself. Once you simplify the last one, substitute -2 for and do the arithmetic. John My calculator said it, I believe it, that settles it
 Numbers_Word_Problems/372259: Suppose you take 2 1/2h to drive from your house to the lake at 48 mi/h. How long will your return trip take at 40 mi/h?1 solutions Answer 265177 by solver91311(16877)   on 2010-11-16 19:22:59 (Show Source): You can put this solution on YOUR website! Distance equals rate times time, so the distance to the lake is 2 1/2 hours times 48 miles per hour. Then, presuming no one moved your house while you were gone, time equals distance divided by rate, in other words, the results of your first calculation divided by 40 mph. John My calculator said it, I believe it, that settles it
 Coordinate-system/372257: graph the lines containing these points and find their slope 1 solutions Answer 265175 by solver91311(16877)   on 2010-11-16 19:20:05 (Show Source): You can put this solution on YOUR website! Sure thing, Sparky. I'll just get out my crystal ball and divine the coordinates of your points. Are you new or something? John My calculator said it, I believe it, that settles it
 Average/372249: The coordinates are (15,80) for the helicopter and (55,38) for the boat. A Coast Guard Helicopter receives a distress signal from a boat. The units on the map represent miles. To the nearest minute, how long will it take the helicopter to reach the boat if the helicopter travels at an average speed of 75 mph?1 solutions Answer 265174 by solver91311(16877)   on 2010-11-16 19:18:21 (Show Source): You can put this solution on YOUR website! Use the distance formula: where and are the coordinates of the given points. Then time equals distance divided by rate. Divide the results of your distance calculation by 75. Multiply that result by 60 and round to the nearest whole number. John My calculator said it, I believe it, that settles it
 Average/372250: On a map of a city park, the ordered pairs (3,5) and (8,17) mark the starting and ending points of a straight jogging trail. Each unit on the map represents 0.1 mile. What is the length of the trail in miles? How many back-and-forth trips would Marisol need to make one the trail in order to run at least 7 miles?1 solutions Answer 265173 by solver91311(16877)   on 2010-11-16 19:15:10 (Show Source): You can put this solution on YOUR website! Use the distance formula: where and are the coordinates of the given points. Multiply your answer by 0.1 to get the length of the trail in miles. Multiply that result by 2 to get the round trip distance. Divide that result into 7. Round up. And it is the same answer even if her name is something other than Marisol. John My calculator said it, I believe it, that settles it
 Graphs/372233: why is the line x-4 a vertical line1 solutions Answer 265168 by solver91311(16877)   on 2010-11-16 19:09:44 (Show Source): You can put this solution on YOUR website! It isn't. is simply a binomial expression in one variable. Now if you make it equal to something, such as zero, THEN you have an equation whose graph and/or solution set is a straight line, and in this particular case, a vertical line. The reason it is a vertical line is that the set of points that comprise the solution set of the equation all have an ordinate, or -coordinate, of the value 4. All points with an -coordinate of 4 must lie on a vertical line. Go ahead and try to find a point with an -coordinate of 4 that is NOT on the vertical line . John My calculator said it, I believe it, that settles it
 Quadratic_Equations/372236: v^2 + 6v - 46 = 9 Can you show me step by step solving v be completing the square? thanks1 solutions Answer 265166 by solver91311(16877)   on 2010-11-16 19:03:46 (Show Source): You can put this solution on YOUR website! Add 46 to both sides. Divide the coefficient on v by 2 and square the result. Add that result to both sides. Factor the perfect square trinomial in the LHS. Take the square root of both sides, remembering to consider both the positive and negative roots. Add the opposite of the constant term in the LHS to both sides, leaving you with v in the LHS and the two roots in the RHS. John My calculator said it, I believe it, that settles it
 Length-and-distance/372242: j(2,-1),k(2,5) find the distance between the points to the nearest tenth1 solutions Answer 265163 by solver91311(16877)   on 2010-11-16 18:58:41 (Show Source): You can put this solution on YOUR website! Use the distance formula: where and are the coordinates of the given points. John My calculator said it, I believe it, that settles it
 Numbers_Word_Problems/372234: Can you please help me set this problem up? The sum of the digits of a two-digit number is 14. If the digits are reversed, the new number is 18 less than the original number. Find the original number.1 solutions Answer 265161 by solver91311(16877)   on 2010-11-16 18:57:25 (Show Source): You can put this solution on YOUR website! Let be the original 10s digit and let be the original 1s digit. First we are given that: And then: Collecting terms: So solve the system: John My calculator said it, I believe it, that settles it
 Numbers_Word_Problems/372223: the sum of two numbers is six. the sum of the squares of the two numbers is twenty. find the two numbers1 solutions Answer 265159 by solver91311(16877)   on 2010-11-16 18:50:53 (Show Source): You can put this solution on YOUR website! Let represent one of the numbers, then the other number must be . Then: Solve for . John My calculator said it, I believe it, that settles it
 Geometry_proofs/372213: How do you prove the median from the vertex angle of an isos. triangle is also an angle bisector?1 solutions Answer 265157 by solver91311(16877)   on 2010-11-16 18:46:37 (Show Source): You can put this solution on YOUR website! The median from the vertex angle bisects the base forming two triangles. The base angles are equal and the long sides of the two formed triangles are equal because the original triangle was isosceles. So by SAS the two formed triangles are congruent and therefore the two angles formed at the vertex by the median are congruent by CPCT. John My calculator said it, I believe it, that settles it
 Polynomials-and-rational-expressions/372205: Are the expressions 2x to the third power and (2x) to the third power equivalent? ) Is the operation of raising to a power comunitiative? That is, is a to the b power = to b to thhe a power? Explain why or why not. 2) Explain in detail the steps involved in finding the product of two polynomials. Use an example if you wish. 3) 4) Describe the steps involved, in detail, in finding the product of x+2 and x-2. 4) 5) Describe how to determine if a sum of terms is a polynomial. Illustrate with an example of a polynomial and a non-polynomial 1 solutions Answer 265141 by solver91311(16877)   on 2010-11-16 18:24:26 (Show Source): You can put this solution on YOUR website! Go back and re-read the instruction that says "One question per post." Then follow the written instructions in your future posts. John My calculator said it, I believe it, that settles it
 Exponents/372200: Ok thanks for the help now here is my question. 7^5/7^3 Now you may already know that the arrow pointing up is the exponent sign. And that is supposed to be a fraction, 7 to the 5th power over 7 to the third power. Now, my homework says to evaluate the expression. Write your answer as a fraction in simplest form. How do i do that? Please help. What i did was just find the answer to 7^5 which was 16807 and then i found the answer to 7^3 which was 343. I put 16807 on top of 343 ( 16807/343 ). You cant reduce that so i thought it would be the right answer. But it doesnt feel right. So please try and help. Thanks.1 solutions Answer 265136 by solver91311(16877)   on 2010-11-16 18:19:16 (Show Source): You can put this solution on YOUR website! Yes, that is exactly right, just the L - O - N - G way to get there. 16807 divided by 343 is 49 which is the correct answer. However, the quick and easy way to do this one is to use the following law of exponents: For your problem, 5 minus 3 is 2, and 7 squared is 49. John My calculator said it, I believe it, that settles it
 Matrices-and-determiminant/372188: to solve a system of equations with cramer's rule what is the correct order?1 solutions Answer 265132 by solver91311(16877)   on 2010-11-16 18:13:22 (Show Source): You can put this solution on YOUR website! What do you mean by "correct order?" John My calculator said it, I believe it, that settles it
 test/372191: 2% of the containers made by a manufacturer are defective. If 750 of the containers are inspected, how many can be expected not to be defective? 1 solutions Answer 265128 by solver91311(16877)   on 2010-11-16 18:11:23 (Show Source): You can put this solution on YOUR website! John My calculator said it, I believe it, that settles it
 Polynomials-and-rational-expressions/372190: Please help: 0.7m=0.9m + 2.4 - 0.2m It can have no solution or be 'identity'1 solutions Answer 265126 by solver91311(16877)   on 2010-11-16 18:07:17 (Show Source): You can put this solution on YOUR website! Combine like terms in the RHS: Add -0.7m to both sides: So, what values of will make ? John My calculator said it, I believe it, that settles it
 Linear_Algebra/372192: hi, im doing linear functions so, what is f(x)=2x to the third power or cubes, please help me!!!! 1 solutions Answer 265125 by solver91311(16877)   on 2010-11-16 18:03:55 (Show Source): You can put this solution on YOUR website! It is certainly not a linear function. It is a third degree polynomial function. John My calculator said it, I believe it, that settles it
 Polynomials-and-rational-expressions/372186: Please help me figure out this equation. 3/4x = 1/2 + 2/3x1 solutions Answer 265124 by solver91311(16877)   on 2010-11-16 18:02:34 (Show Source): You can put this solution on YOUR website! Depends. Do you mean what I think you mean, namely: ? Or do you mean what you wrote: ? Re-post using parentheses to eliminate ambiguity and misunderstanding. John My calculator said it, I believe it, that settles it
 Geometry_Word_Problems/372184: At the end of a year, a tree has split into two branches. At the end of each succeeding year, each branch has split into two more branches. How many branches are there at the end of nine years? 1 solutions Answer 265120 by solver91311(16877)   on 2010-11-16 17:53:57 (Show Source): You can put this solution on YOUR website! is the number of branches that grew during the last year, but you need that plus the previous year plus the year previous to that...and so on back to the beginning. But since You need John My calculator said it, I believe it, that settles it
 Percentage-and-ratio-word-problems/372178: A class grade is based on two parts,70% of a total grade at is 95%, 30% of the total grade is x, what does x need to be to maintain an overall grade of 90% for the class? 1 solutions Answer 265117 by solver91311(16877)   on 2010-11-16 17:46:25 (Show Source): You can put this solution on YOUR website! Solve for . John My calculator said it, I believe it, that settles it
 Systems-of-equations/372172: how to solve algebra systems of equations by eliminating and combing 1 solutions Answer 265112 by solver91311(16877)   on 2010-11-16 17:41:41 (Show Source): You can put this solution on YOUR website! In the first place "combing" might make your hair look nice, but won't do much of anything for a system of equations. If you have a system of two equations in two variables: Multiply one or the other or both of the equations by a constant or constants so that the coefficients on one of the variables become additive inverses. Add the two equations term by term so that one of the variables is eliminated. Solve the resulting single variable equation. Take the value you just determined and substitute back into either of the original equations and then solve the resulting single variable equation for the other variable. If you have more than two equations and an equal number of variables, you may have to repeat the above steps several times to reduce one of the equations to a single variable equation. Systems larger than 3X3 are more easily solved by other methods such as Row Reduction. John My calculator said it, I believe it, that settles it
 Travel_Word_Problems/372169: If you are 16 miles from Ann Arbor,how long will it take to get there if your average speed is 42 miles per hour?1 solutions Answer 265105 by solver91311(16877)   on 2010-11-16 17:34:11 (Show Source): You can put this solution on YOUR website! Distance equals rate times time, so time equals distance divided by rate. Divide 16 by 42. John My calculator said it, I believe it, that settles it
 Permutations/372166: A computer with an old processor locks up if more than 4 applications are running simutaniously. If the owner has 20 applications stored in his program file, how many different sets of 4 can he run, so that his computer does not lock up? 1 solutions Answer 265103 by solver91311(16877)   on 2010-11-16 17:31:18 (Show Source): You can put this solution on YOUR website! How many ways can you select 4 things out of 20 things where order doesn't matter? The arithmetic is all yours. John My calculator said it, I believe it, that settles it
 Geometry_Word_Problems/372144: American astronauts working on the space station toss a ball into the air. the height of the ball is represented by the quadratic y=-2.7x^2+13.5x+14, where x represents the number of seconds since the ball was thrown and y represents the height of the ball in feet. a) to the nearest hundredth of a second, after how much time does the ball hit the ground? b) to the nearest tenth of a foot, what is the greatest height the ball achieves? 1 solutions Answer 265101 by solver91311(16877)   on 2010-11-16 17:29:06 (Show Source): You can put this solution on YOUR website! To answer the questions precisely as you posed them would require knowing the distance from the surface of the earth to the space station plus a bunch of data and physics about the orbital decay of a ball left in earth orbit. This is in view of the fact that "the ground" is back on earth. On the other hand, if what you really meant to ask is: a) to the nearest hundredth of a second, after how much time does the ball hit the deck of the space station above which the ball was thrown? b) to the nearest tenth of a foot, what is the greatest height above the deck of the space station the ball achieves? Then for part a: Set the quadratic equal to zero and solve for the positive root. And for part b: Evaluate the function at the x-coordinate of the vertex of the parabola. The x-coordinate of the vertex of is found by calculating . Evaluating the function at that point means calculating and then rounding appropriately, of course. John My calculator said it, I believe it, that settles it
 Problems-with-consecutive-odd-even-integers/372148: A SQUARE POSTER HAS SIDES MEASURING 2 FEET LESS THAN THE SIDES OF A SQUARE SIGN. IF THE DIFFERENCE BETWEEN THEIR AREAS IS 20 SQUARE FEET, FIND LENGTHS OF THE SIDES OF THE POSTER AND THE SIGN.1 solutions Answer 265088 by solver91311(16877)   on 2010-11-16 17:14:55 (Show Source): You can put this solution on YOUR website! Typing in all caps is the electronic communications equivalent of shouting. It is both annoying and rude. Let represent the measure of the side of the larger square. Then is the measure of the side of the smaller square, is the area of the smaller square, and is the area of the larger square. Solve for for the sides of the sign, subtract 2 for the sides of the poster. John My calculator said it, I believe it, that settles it
 Quadratic_Equations/372140: If I have a solution how can I create a quadric equation 1 solutions Answer 265084 by solver91311(16877)   on 2010-11-16 17:08:20 (Show Source): You can put this solution on YOUR website! You can't, in general. That is because you need two solutions to create a quadratic. However, in some cases, the character of the solution that you do have allows you to deduce the solution that you don't have. For example, if you have a solution that looks like Then, because of symmetry, the other solution is guaranteed to be: . Likewise, if you have a single complex number solution, then the other solution is the conjugate of that complex number. On the other hand, if you only have one rational number solution, you are at a dead end, unless you know that your single rational solution has a multiplicity of two. Given that you do have two solutions, let's call them and , all you have to do is calculate the product: And set that product equal to zero. In the case where you have one solution with a multiplicity of two, meaning you have two identical solutions, you can calculate: John My calculator said it, I believe it, that settles it
 Probability-and-statistics/372000: If there are 60 questions on an exam, the succes rate is 1/4. You know 24 out of 60 questions, what is the probability you will suceed on the exam if the passing grade is 50%.1 solutions Answer 264992 by solver91311(16877)   on 2010-11-16 13:15:14 (Show Source): You can put this solution on YOUR website! The probability of successes in trials where is the probability of success on any given trial is given by: Where is the number of combinations of things taken at a time and is calculated by Given that you know 24 out of the 60, you need the probability of guessing at least 6 out of 36 with a per question probability of . You can go about this one of two ways. The probability of at least 6 correct out of 36 is the probability of exactly 6 plus exactly 7 plus exactly 8 ... plus exactly 35, plus exactly 36. Symbolically: Which, trust me, is a very long, tedious, and therefore highly error prone calculation in that the sum consists of 31 terms, several of which have coefficients in the billions. However, there is an easier way. Note that the probability of getting 5 or less correct PLUS the probability of getting 6 or more correct is just 1, or certainty -- if you guess at 36 questions it is an absolute certainty that you will get between 0 and 36 of them correct. Hence the desired probability is 1 minus the probability of getting 5 or less correct: which sum only has 7 terms (counting the 1) and the largest coefficient is 58905. Get out your calculator and get cracking. You should get an answer that is between 91 and 92 percent. John My calculator said it, I believe it, that settles it