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Exponents-negative-and-fractional/153508: This question is from textbook Algebra structure and method book 1 can you please help me: (((Graph the equation x-y=6))) 1 solutions Answer 113003 by Fombitz(13828)   on 2008-08-26 13:32:28 (Show Source): You can put this solution on YOUR website! The best way to start is to re-arrange the equation to the form y=...., then you can stick x values in and get y values out quickly. Now choose a range of x you want to plot. Let's go from -5 to 5 in steps of 1. Plug in x to get y. y=x-6 y(-5)=-5-6=-11 (-5,-11) y(-4)=-4-6=-10 (-4,-10) y(-3)=-3-6=-9 (-3,-9) You're starting to see a pattern here. Each step in y produces one step in x. We can just list the remaining pairs. (-2,-8) (-1,-7) (0,-6) (1,-5) (2,-4) (3,-3) (4,-2) (5,-1) Now plot the points on a graph. . . . Then draw the straight line between them. .

Numeric_Fractions/153525: How can you tell what a negative slope is and a positive sole is? 1 solutions Answer 113002 by Fombitz(13828)   on 2008-08-26 13:23:21 (Show Source): You can put this solution on YOUR website! As you look at the graph from left to right (increasing x), if the line is going up(increasing y), slope is positive. . . . If it's going down (decreasing y), slope is negative. . . . If it's horizontal (constant y), slope is zero.

Quadratic_Equations/153526: This question is from textbook Intermediate Algebra I can't seem to get the formula right to solve problem. Can someone help? The problem is to use the quadratic formula to solve the equation: x^2-11x+30=0 Thanks for your help! 1 solutions Answer 113001 by Fombitz(13828)   on 2008-08-26 13:17:27 (Show Source): You can put this solution on YOUR website! . . . . . .

Probability-and-statistics/153491: A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were 3.087 3.131 3.241 3.241 3.270 3.353 3.400 3.411 3.437 3.477 a). Construct a 90 percent confidence interval for the true mean weight. (b) What sample size would be necessary to estimate the true weight with an error of ± 0.03 grams with 90 percent confidence? (c) Discuss the factors which might cause variation in the weight of Tootsie Rolls during manufacture. 1 solutions Answer 112997 by Fombitz(13828)   on 2008-08-26 10:31:50 (Show Source): You can put this solution on YOUR website! a)Since you don't know and your sample size is <30, assume your samples are normally distributed. Use the t-distribution as the best estimate. Degrees of freedom are n-1 or 9. . . . The calculated mean,, is 3.3048. The calculated standard deviation, , is 0.132 For and , . . . . The confidence interval is . . . b) Working backwards, t is a function of n so you have to iterate to find n. I set up an iteration cell in EXCEL using TINV and varying n. n=54 gives 54 samples required to give For this large a value for n, we can use the normal distribution as a check of the value since as n gets large the t distribution approaches the normal distribution. z=1.65 for 90% Use the calculated 0.132 as an estimate for or Good, that's close. . . . c) Factors include length errors from cutting machine, air in the mixture, humidity in the plant, density changes in the mixture, etc.

Expressions-with-variables/153498: I need the steps to this please Solve 64x^2-49=0 1 solutions Answer 112992 by Fombitz(13828)   on 2008-08-26 09:51:07 (Show Source): You can put this solution on YOUR website! Sorry about the zero but the +/- sign won't show up without it.

Equations/153501: I need help with solving this equation and how to get the answer. The question is 2/7J - 1/7 = 3/14 1 solutions Answer 112991 by Fombitz(13828)   on 2008-08-26 09:48:20 (Show Source): You can put this solution on YOUR website! Is it or is it ??

Miscellaneous_Word_Problems/153502: condense the esspression 1/2ln(x+1)-1/2ln(x-1)+lnC 1 solutions Answer 112990 by Fombitz(13828)   on 2008-08-26 09:46:15 (Show Source): You can put this solution on YOUR website! Substitute a=(1/2) for better clarity In final form,

Linear-equations/153499: Please help me with these problems 1. Find the equation in standard form,with all integer coefficients of the line perpendicular to x- 2y = 24 and passing through (1,3) 2.Solve the system of equation using the addition (elimination method)if the answer is a solution present it in ordered pair(x,y) if not specify wheather it a "no solution or "infinite many solution" x + 2y = 5 3x + 4y = 1 1 solutions Answer 112989 by Fombitz(13828)   on 2008-08-26 09:39:05 (Show Source): You can put this solution on YOUR website! 1. First find the slope of this line. The slope is (1/2). Perpendicular lines have slopes that are negative reciprocals. Now use the point slope form of a line with the slope and point(1,3), Standard form . . . 1. 2. Multiply eq. 1 by (-2) and add to eq. 2, 1. 2. From 1, 1. One unique solution (-9,7).

Miscellaneous_Word_Problems/153488: use the change of base formula to write an expression in termsof logarithms to base e for log5 10. what is the value (nearest 0.01) 1 solutions Answer 112988 by Fombitz(13828)   on 2008-08-26 09:26:20 (Show Source): You can put this solution on YOUR website!

Miscellaneous_Word_Problems/153489: find the zeros of the function f(x)=xe^-x -e^-x 1 solutions Answer 112987 by Fombitz(13828)   on 2008-08-26 09:20:04 (Show Source): You can put this solution on YOUR website!

Miscellaneous_Word_Problems/153480: Please help me with some word problems. I have tried for several hours and cant figure out where to begin. Sarah has three times as many dimes as nickels and twice as many quarters as dimes. In all, she has $5.55. How many of each coin does she have? Thank you. 1 solutions Answer 112985 by Fombitz(13828)   on 2008-08-26 09:15:08 (Show Source): You can put this solution on YOUR website! First, name your variables. Q for quarters, D for dimes, N for nickels. If she has N nickels, she has 3N dimes (three times as many). If she has N nickels, she has 2N quarters (twice as many). 1. 2. Each nickel is worth $0.05, each dime $0.10, and each quarter $0.25. The total value is $5.55. Let's multiply both sides by 100 to get rid of decimals. 2. Substitute eq. 1 and eq. 2 into eq. 3 and solve for N. 2. From above, 1. 2. Check your answer True, good answer.

Miscellaneous_Word_Problems/153490: solve the equation e^5x-3=10 1 solutions Answer 112983 by Fombitz(13828)   on 2008-08-26 09:00:48 (Show Source): You can put this solution on YOUR website! I'm assuming this is your equation (not sure w/o parentheses), Natural log of boths sides. or approximately, . . . If your equation was,

Miscellaneous_Word_Problems/153496: Solve the equation exactly for x: log3 x-log3(x-3)=2 1 solutions Answer 112982 by Fombitz(13828)   on 2008-08-26 08:55:06 (Show Source): You can put this solution on YOUR website!

Expressions-with-variables/153322: I need the steps to this Add the polynomials 3x^2-5x+7 and 4x^2+8x-3 1 solutions Answer 112891 by Fombitz(13828)   on 2008-08-25 16:28:37 (Show Source): You can put this solution on YOUR website! Add like terms (x^2 terms, x terms, constants):

Expressions-with-variables/153370: what is a expression for the number of months in y years 1 solutions Answer 112890 by Fombitz(13828)   on 2008-08-25 16:25:41 (Show Source): You can put this solution on YOUR website! There are 12 months in one year, so there would be 12*y in y years.

Exponents/153332: The response to my question 153330 is incorrect The equation is 4topower 3 < 5to power 5=4power8 it does not makes sense....or am i missing something 1 solutions Answer 112889 by Fombitz(13828)   on 2008-08-25 16:24:04 (Show Source): You can put this solution on YOUR website! You're saying that the problem looks like this: If that's it, then you're right, it doesn't make sense.

Inequalities/153355: How do I express the answer to the following inequality in interval notation? (y-3)/3> 1/3-(y-5)/6 1 solutions Answer 112888 by Fombitz(13828)   on 2008-08-25 16:19:54 (Show Source): You can put this solution on YOUR website! By solving the equation for y and finding the interval where it is valid. Multiply by 6 to get rid of denominators.

test/153329: This question is from textbook Algebra 1 An Incremental Development Complete: If f(x)= (x+2)/3, then the value of f(0) equals ______ 1 solutions Answer 112856 by Fombitz(13828)   on 2008-08-25 11:01:39 (Show Source): You can put this solution on YOUR website! Substitute 0 for each occurence of x.

Exponents/153330: My daughter is doing a summer math packet and we seem to have answered most problems by using the examples to work from but one example I cannot make any sense of....I do not know the sign it is using The example is 4 to the power 3 < 5 to the power 5 = 4 to the power 8??? I have tried resolving the numbers 64<3125 = 65,536.....I cannot find a relationship that makes this work....HELP PLEASE!!!! 1 solutions Answer 112855 by Fombitz(13828)   on 2008-08-25 11:00:36 (Show Source): You can put this solution on YOUR website! Is looks like a true/false question? It would be true. Am I missing something?

Expressions-with-variables/153318: I need the steps for this please Find an equation for the line with undefined slope and passing through the point (9-7) 1 solutions Answer 112854 by Fombitz(13828)   on 2008-08-25 10:51:05 (Show Source): You can put this solution on YOUR website! Let's look at the formula for the slope of the line, For the slope to be undefined the denominator must equal 0. All x values must be the same. Given the point, (9,-7), then the equation is

Geometry_Word_Problems/153317: Hello, How would I graph the following: Plot the graphs of the following functions. Scan the graphs and post them to the Facilitator along with your response. 3. f(x)=(1/5)^x Thank you, Jimmy 1 solutions Answer 112852 by Fombitz(13828)   on 2008-08-25 10:39:27 (Show Source): You can put this solution on YOUR website! Make a table of x,f(x) data points. Then plot the points and connect the points. -2 ,25 -1 ,5 0 ,1 1 ,0.2 2 ,0.04 3 ,0.008 As you can see from the points as x grow large negatively, f(x) increases quickly. Also, as x grows large positively, f(x) quickly goes to zero.

Exponents-negative-and-fractional/153304: This question is from textbook Algebra structure and method book 1 can you help me:(((write an equation for the line going through the points (3,2) and (-2,4)))) 1 solutions Answer 112841 by Fombitz(13828)   on 2008-08-25 10:03:42 (Show Source): You can put this solution on YOUR website! First find the slope of the line using the two point slope formula, Then us the point-slope form of the line using one of the points and the slope. I'll use (-2,4) as the point.

Matrices-and-determiminant/153215: Create a "2 by 3" matrices Directions 1. add them together 2. subtract them 3. multiply them by the scalar 4. I set up the problem below, but having trouble solving it. please help me. due tomorrow!!!!!!!!! 4 {3,4,5,2,11,6} 1 solutions Answer 112840 by Fombitz(13828)   on 2008-08-25 09:52:44 (Show Source): You can put this solution on YOUR website! 1. 2. 3.

Triangles/153244: what is value of x . In a trinagle 1 solutions Answer 112839 by Fombitz(13828)   on 2008-08-25 09:45:30 (Show Source): You can put this solution on YOUR website! Please re-post your question. You have missing information.

Probability-and-statistics/153281: 3 missionaries and three cannibals must cross a river How do they cross using only one boat and at no time letting the cannibals outnumber the missionaries on either side of the river. 1 solutions Answer 112838 by Fombitz(13828)   on 2008-08-25 09:44:19 (Show Source): You can put this solution on YOUR website! All three missionaries and all three cannibals get in the boat and cross the river together. Are you sure you're not missing part of the problem in your explanation such as the max. number of people in the boat.

Inequalities/153063: Find all the solutions of given that -2 is a root 1 solutions Answer 112519 by Fombitz(13828)   on 2008-08-22 15:55:02 (Show Source): You can put this solution on YOUR website! Since -2 is a root then (x+2) is one factor of the equation. You can divide the original polynomial by (x+2) to find the quadractic factor. Now find the roots of . Using the quadratic formula, The solutions are and .

Equations/152999: This question is from textbook I cannot figure out the restrictions, i am completely confused!! 6/x+3-5/x-2=-20/x^2+x-6 1 solutions Answer 112507 by Fombitz(13828)   on 2008-08-22 14:10:24 (Show Source): You can put this solution on YOUR website! The restrictions are that the solution for x cannot allow the denominators to equal zero. Therefore x cannot be 2 or -3.

Geometric_formulas/152979: derive the formula of the following: 1. rectagular prism 2. triangular prism 3. cylindrical prism 4. pyramid 1 solutions Answer 112506 by Fombitz(13828)   on 2008-08-22 14:04:37 (Show Source): You can put this solution on YOUR website! Please repost your question. The formula for what??? Area,Volume,etc.

Equations/153049: The lenght of a rectangle is 5cm longer than three times its width. The perimeter is 74cm. Find the width and lenght. 1 solutions Answer 112505 by Fombitz(13828)   on 2008-08-22 13:52:51 (Show Source): You can put this solution on YOUR website! "lenght of a rectangle is 5cm longer than three times its width" 1. "The perimeter is 74cm." 2. Use eq. 1 in eq. 2 and solve for W. 1. "The perimeter is 74cm." 2. From 1, 1.

Equations/153046: A plane flies against the wind from Center City to New City at a rate of 220mph. On the return trip, the plane flies with the wind at a rate of 250mph.The return trip took one hour less time. How far apart are the two cities? (remember rt=d) 1 solutions Answer 112504 by Fombitz(13828)   on 2008-08-22 13:41:15 (Show Source): You can put this solution on YOUR website! Let's call the time from Center to New, T. 1. The return trip took 1 hour less, or T-1. 2. Since they're both equal to D, they're equal to each other. Using eq. 1, It is 1833 miles from New City to Center City.

Distributive-associative-commutative-properties/153051: Please explain how to reverse FOIL when factoring a polynomial of the form ax(squared) + bx + c when a = 1 and when a does not = 1. 1 solutions Answer 112501 by Fombitz(13828)   on 2008-08-22 13:28:54 (Show Source): You can put this solution on YOUR website! Here's a general quadratic equation using FOIL, As you can see it can be complicated. Typically a=1, so you can make the assumption that d=f=1. This is not always true because you could have d=2 and f=1/2, then a=df=1. When a is not 1, then it becomes more difficult because there are more choices to check. . . . Best bet is always start at c and look for its factors, e and g. If a=1 it becomes easier. The middle term (the x term) is just e+g. If a does not equal 1, you can still do it but your number of guesses increases until you hit that right combination of d,e,f,g. . . . Best bet is to become more familiar with combinations of numbers multiplied together and then added. As an example, take 5 and 8. Let's not worry if they're positive or negative. Multiplied, they're 40(-40). If they're added or subtracted you could get (-13,-3,3,13) So from 5 and 8 you can get . . . If you look at the case where a is not equal 1, it can be more tricky, Best bet is always start with the easiest possible solution guess, If a=3 then start with If a=4, then the simplest choices would be, As you can see if a has a lot of factors the number of choices grows quickly. It can be tedious but there are only a limited number of possibilities. Good luck.