Finalshine Posted March 9, 2014 Share Posted March 9, 2014 Im Using a Cas Calculator to work out the Following Equation x+11 2(x+14x) ------- = --------- 3 9Now i no the Answer is -5 but when putting the following Equation in my Calculator i keep comimg up with 11x= ---- 9Just looking for a bit of Help if any one can help me at all.. thanks Matt Link to comment Share on other sites More sharing options...

hypervalent_iodine Posted March 9, 2014 Share Posted March 9, 2014 Are you sure it equals -5? I worked it out manually and came to the same answer as your calculator and substituting -5 in for x gives 2 = -16.67 which obviously is incorrect. Link to comment Share on other sites More sharing options...

Finalshine Posted March 9, 2014 Author Share Posted March 9, 2014 (edited) this is the equation im doing, but my text book says its -5 Edited March 9, 2014 by Finalshine Link to comment Share on other sites More sharing options...

John Posted March 9, 2014 Share Posted March 9, 2014 Textbooks often contain typos. You should solve the equation by hand and see what you find. At the very least, try plugging in -5 and then 11/9, as hypervalent_iodine did, and see which value results in a true statement. Link to comment Share on other sites More sharing options...

Unity+ Posted March 9, 2014 Share Posted March 9, 2014 I also got 11/9. (x+11)/3=2(x+14x)/9 (x+11)/3=2(15x)/9 (11/9+11)/3=2(15(11/9))/9 (11/9+99/9)/3=2(55/3)/9 110/9/3 = 110/3/9 110/27 = 110/27 Link to comment Share on other sites More sharing options...

imatfaal Posted March 9, 2014 Share Posted March 9, 2014 Hang on Hang on. What sort of text book writes 30x as 2(x+14x)?! I would bet a pound to a penny that it is not the answer which is wrong but the equation - either in the printing of the text or in the transcription [latex]\frac{x+11}{3}=\frac{2(x+14x)}{9}[/latex] is awful similar to [latex]\frac{x+11}{3}=\frac{2(x+14)}{9}[/latex] which is a much more normal way of writing things [latex]\frac{x+11}{3}=\frac{2(x+14)}{9} [/latex] [latex]\frac{9(x+11)}{3}=2(x+14) [/latex] [latex]3(x+11) = 2(x+14)[/latex] [latex]3x +33 = 2x +28[/latex] [latex]3x-2x = 28-33[/latex] [latex]x = -5[/latex] 6 Link to comment Share on other sites More sharing options...

Unity+ Posted March 9, 2014 Share Posted March 9, 2014 Hang on Hang on. What sort of text book writes 30x as 2(x+14x)?! I would bet a pound to a penny that it is not the answer which is wrong but the equation - either in the printing of the text or in the transcription [latex]\frac{x+11}{3}=\frac{2(x+14x)}{9}[/latex] is awful similar to [latex]\frac{x+11}{3}=\frac{2(x+14)}{9}[/latex] which is a much more normal way of writing things [latex]\frac{x+11}{3}=\frac{2(x+14)}{9} [/latex] [latex]\frac{9(x+11)}{3}=2(x+14) [/latex] [latex]3(x+11) = 2(x+14)[/latex] [latex]3x +33 = 2x +28[/latex] [latex]3x-2x = 28-33[/latex] [latex]x = -5[/latex] I was originally thinking that the book was going into simplification(combining like terms) because it was weird how a textbook would present the equation as such. Good eye, I must say. Link to comment Share on other sites More sharing options...

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