document.write( "Question 95014: Place parentheses to make the following equation true\r
\n" ); document.write( "\n" ); document.write( "13 - 4 x 5 / 2 +10 = 13
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Algebra.Com's Answer #69138 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given:
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\n" ); document.write( "13 - 4 x 5 / 2 +10 = 13
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\n" ); document.write( "Let's replace the x with the multiplication symbol *. It doesn't change the problem, but
\n" ); document.write( "it makes it a little easier to read because we won't confuse the x (meaning times) with the
\n" ); document.write( "letter x which is often used as an unknown in algebra. So the given equation becomes:
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\n" ); document.write( "13 - 4 * 5/2 +10 = 13
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\n" ); document.write( "How about if we put parentheses around the middle term to set it apart as follows:
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\n" ); document.write( "13 -((4*5)/2) + 10 = 13
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\n" ); document.write( "The parentheses now make this problem in the textbook form:
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\n" ); document.write( "\"13+-%28%284%2A5%29%2F2%29+%2B+10+=+13\"
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\n" ); document.write( "Notice that the 4*5 is 20 and when you divide that by the 2 you get 10. This reduces
\n" ); document.write( "the problem to:
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\n" ); document.write( "\"13+-+10+%2B+10+=+13\"
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\n" ); document.write( "And the -10 and +10 cancel each other out, so the problem is reduced to:
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\n" ); document.write( "\"+13+=+13\"
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\n" ); document.write( "This is a true statement, so by using the parentheses the way we did we made the given problem
\n" ); document.write( "much easier to understand because it was then in the correct form.
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\n" ); document.write( "The lesson here is that using parentheses can really help to clarify a problem. You see
\n" ); document.write( "a lot of students in this forum write things such as:
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\n" ); document.write( "2/x+7
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\n" ); document.write( "According to the rules governing the order of operations, this means:
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\n" ); document.write( "\"2%2Fx+%2B+7\"
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\n" ); document.write( "but you wonder if they didn't mean to write 2/(x+7) which is completely different
\n" ); document.write( "because it means:
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\n" ); document.write( "\"2%2F%28x%2B7%29\"
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\n" ); document.write( "That lack of clarity causes some tutors to disregard the problem because they don't know
\n" ); document.write( "which version they should work and they may just confuse the student by working the wrong
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\n" ); document.write( "Hope this helps you to understand the importance of parentheses. It sure doesn't hurt
\n" ); document.write( "to use them to make sure you are communicating what you mean in a problem.
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