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I think we have an error in our pre-algebra book. How would you simplify this equation? 12b + -8b + + b. The answer in the book is 41/2b

12b+ -8b + + b How would you simplify this problem? The answer in the back of uour book says: 41/2b I wouls simplify it as:5b What is the correct answer?


When you come across errors in your textbook to which you have proof (have the right answer), you can write the publisher and let them know. Include the title of the textbook, author(s), edition, and publication year of your book; the page number and problem number; the original problem and the recommended solution. Then include how your solve the problem and the correct answer. Next time the publisher publishes the next edition of the book, the corrections should be included. You can send the information in yourself, ask your teacher, or your parents to help you.

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Allan S. | Tutor Available for Math, Science and Computer subjectsTutor Available for Math, Science and Co...
4.8 4.8 (103 lesson ratings) (103)

rewite the expression as follows:


(12b) + (-8b) + (+b)

this makes each term in the expression more obvious.

now, factor the b out of each term as follows:

b(12-8+1)  =  b(5)  = 5b

Nicole C. | Increase confidence in math and science, chemistry, algebra IIIncrease confidence in math and science,...
4.9 4.9 (167 lesson ratings) (167)
I'm thinking 5b as well, I am a little thrown off by the two back to back + signs though. If there are no fractions in the original problem you shouldn't have a fraction in your answer.


It's funny what typos can be found in text books. I remember once reading about a few and my favorite was where a physics book claimed that the metric unit of mass was the hologram (should be kilogram).