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# How do I enter fractions in Wolfram Alpha ?

Posted 9 years ago
 Good Morning, I am trying to enter the following problem, so I can see the steps to solve it. 3r+6 4r-24 ____ = _____ 9 4 I put it in as 3r+6/9 = 4r-24/4 It interprets it as: Click Here I need it to read 3r plus 6 over 9 equals 4r-24 over 4. Can someone please help explain how to put it in correctly? Thanks in advance!!
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Posted 9 years ago
 Hi Susan,you could use the Solve[] function to solve these equation: Solve[(3 r + 6)/9 == (4 r - 24)/4, r] And if you want to see the step by step solution, you can type in: ==Solve[(3 r + 6)/9 == (4 r - 24)/4, r] The two equals at the beginning of the line, will start the Wolfram|Alpha mode. So you need an internet connection. I hope it helps!
Posted 9 years ago
 I don't know if you just wanted to solve the equation, or if you wanted to see the steps that one might do by hand. In any case, I'm going to show how one might do this for this simple equation.Mathematica automatically removes common factors from the numerator and denominator of fractions. So if you want to show that, you have to take extra measures but first let's go with it and show the remaining steps. Here we annotate the steps with Print statements. We manipulate the equation by using a Pure Function (look up Function in Help) to map the same operation onto both sides of the equation. So the # stands in for each side of the equation. "/@" represents the Map function. Print["Original Equation. Mathematica reduces fractions."] step1 = 3 r + 6/9 == 4 r - 24/4 Print["Consolidate r on the right hand side."] step2 = # - 3 r & /@ step1 Print["Add 6 to both sides."] step3 = # + 6 & /@ step2 Print["Reverse the equation."] Reverse[step3] Now let's do it using symbolic fractions and substituting at the end. We'll just add a to the numbers to turn them into symbols. Print["Original Equation with symbolic fractions."] step1 = 3 r + a6/a9 == 4 r - a24/a4 Print["Clear the denominators on both sides of the equation."] step2 = Distribute[# a9 a4] & /@ step1 Print["Move the rhs r term to the lhs and the lhs constant to the \ rhs."] step3 = # - 4 a4 a9 r - a4 a6 & /@ step2 Print["Divide each side by the r coefficient."] step4 = Distribute[#/(-a4 a9)] & /@ step3 Print["Substitute the fraction values."] step4 /. {a4 -> 4, a6 -> 6, a9 -> 9, a24 -> 24} We really didn't learn much by keeping tract of the numerators and denominators. We might just have used two symbols. You can copy and paste the above code into your Mathematica notebook and evaluate or download the attached notebook. Attachments:
Posted 9 years ago
 I believe that the original poster is asking a question about Wolfram Alpha.If I understand correctly you want Wolfram alpha to divide the entire quantity 3r+6 by 9 rather than just dividing the 6 by 9, correct? And similarly for the expression on the right hand side? So do you want 3r+6/9=4r-24/4  or (3r+6)/9=(4r-24)/4  Either way, to solve these in Wolfram Alpha just ask (for the second case as an example) Solve (3r+6)/9=(4r-24)/4 for r  Then, for the steps to the solution click on "Step-by-step solution" (though this functionality requires a Wolfram Alpha Pro subscription)Take a look here:http://wolfr.am/1oDoZCV
Posted 9 years ago
 Actually, you don't need the "for r" in: Solve (3r+6)/9=(4r-24)/4 for r