document.write( "Question 74333This question is from textbook
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document.write( ": solve the inequality\r
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document.write( " 7q-1+2q<29 \n" );
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Algebra.Com's Answer #53347 by bucky(2189)![]() ![]() ![]() You can put this solution on YOUR website! You can work inequalities like these just as you would an equation with the exception that \n" ); document.write( "if you divide or multiply both sides by a negative number, you need to reverse the direction of \n" ); document.write( "the inequality sign. \n" ); document.write( ". \n" ); document.write( "Let's treat this problem just like an equation that we would solve for q. \n" ); document.write( ". \n" ); document.write( "7q - 1 + 2q < 29 \n" ); document.write( ". \n" ); document.write( "On the left side, combine the two terms by adding 7q and 2q to get: \n" ); document.write( ". \n" ); document.write( "9q - 1 < 29 \n" ); document.write( ". \n" ); document.write( "Eliminate the -1 on the left side by adding +1 to both sides to get: \n" ); document.write( ". \n" ); document.write( "9q < 30 \n" ); document.write( ". \n" ); document.write( "Now divide both sides by +9 in order to solve for q. This results in: \n" ); document.write( ". \n" ); document.write( "q < (30/9) \n" ); document.write( ". \n" ); document.write( "And dividing the both numerator and denominator by 3 reduces the fraction 30/9 to 10/3 \n" ); document.write( "which is equivalent to \"3 and 1/3\" \n" ); document.write( ". \n" ); document.write( "q < 10/3 \n" ); document.write( ". \n" ); document.write( "The solution to this problem is that q can be any value smaller than 10/3. You can help \n" ); document.write( "to convince yourself that this is correct by substituting for a couple values less than \n" ); document.write( "10/3 and seeing that they make the inequality true. Then substitute for q a couple of \n" ); document.write( "numbers that are bigger than 10/3 and see that the equation is not true. \n" ); document.write( ". \n" ); document.write( "Here's a couple of examples. 3 is less than 10/3. If we substitute 3 for q in the original \n" ); document.write( "problem the result is: \n" ); document.write( ". \n" ); document.write( "(7*3) - 1 + (2*3) < 29 \n" ); document.write( ". \n" ); document.write( "which simplifies by multiplication to: \n" ); document.write( ". \n" ); document.write( "21 - 1 + 6 < 29 \n" ); document.write( ". \n" ); document.write( "And by addition rules this reduces to: \n" ); document.write( ". \n" ); document.write( "26 < 29 \n" ); document.write( ". \n" ); document.write( "Which is true. \n" ); document.write( ". \n" ); document.write( "Now let's let q be 4 which is slightly greater than 10/3. The original problem becomes: \n" ); document.write( ". \n" ); document.write( "(7*4) - 1 + (2*4) < 29 \n" ); document.write( ". \n" ); document.write( "which simplifies by multiplication to: \n" ); document.write( ". \n" ); document.write( "28 - 1 + 8 < 29 \n" ); document.write( ". \n" ); document.write( "And by addition rules this reduces to: \n" ); document.write( ". \n" ); document.write( "35 < 29 \n" ); document.write( ". \n" ); document.write( "And this is not true. In this case when q is greater than 10/3 it won't make the inequality true. \n" ); document.write( ". \n" ); document.write( "Notice that in this problem we did not have to multiply or divide both sides by a negative \n" ); document.write( "number so the direction of the inequality remains unchanged from its original direction. \n" ); document.write( ". \n" ); document.write( "Hope this helps you to understand the properties of inequalities a little better. \n" ); document.write( " |