document.write( "Question 724112: It's (3b over 4) minus (1 over 5) = (b over 2) i wanna solve and make b the subject. \n" ); document.write( "

Algebra.Com's Answer #443606 by jsmallt9(3758) $\"\"$ $\"About$

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$\"3b%2F4-1%2F5=b%2F2\"$
\n" ); document.write( "The fastest, easiest way to solve this, IMHO, is to start by eliminating the fractions. To eliminate fractions in an equation, multiply each side by the lowest common denominator (LCD) of all the denominators. The LCD of 4, 5 and 2 is 20. So:
\n" ); document.write( " $\"20%283b%2F4-1%2F5%29=20%28b%2F2%29\"$
\n" ); document.write( "On the left side we must use the Distributive Property:
\n" ); document.write( " $\"20%283b%2F4%29-20%281%2F5%29=20%28b%2F2%29\"$
\n" ); document.write( "As we multiply, each denominator will cancel with some part of the 20:
\n" ); document.write( "15b - 4 = 10b
\n" ); document.write( "The equation is now much easier to solve. Subtracting 10b from each side (so that the b's are all on one side):
\n" ); document.write( "5b - 4 = 0
\n" ); document.write( "Adding 4:
\n" ); document.write( "5b = 4
\n" ); document.write( "Dividing by 5:
\n" ); document.write( "b = 4/5 \n" ); document.write( "

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