document.write( "Question 169630: The area of a rectangle is 15m^2 + 11m - 12. Find the length if the width is 5m-3 \n" ); document.write( "
Algebra.Com's Answer #125053 by gonzo(654)![]() ![]() ![]() You can put this solution on YOUR website! area of a rectangle equals length * width. \n" ); document.write( "let A = area \n" ); document.write( "let L = length \n" ); document.write( "let W = width \n" ); document.write( "A = L*W \n" ); document.write( "----- \n" ); document.write( "you are given the area and the width. \n" ); document.write( "you want to find the length \n" ); document.write( "----- \n" ); document.write( "A = L*W \n" ); document.write( "divide both sides of equation by W: \n" ); document.write( "A/W = L \n" ); document.write( "which is the same as: \n" ); document.write( "L = A/W \n" ); document.write( "----- \n" ); document.write( "A = 15m^2 + 11m - 12 \n" ); document.write( "W = 5m-3 \n" ); document.write( "----- \n" ); document.write( "substitute for A and W: \n" ); document.write( "L = (15m^2 + 11m - 12) / (5m-3) \n" ); document.write( "----- \n" ); document.write( "this is a straight long division problem: \n" ); document.write( "first you figure how many times 5m will divide into 15m^2. \n" ); document.write( "answer is: \n" ); document.write( "3m ********* this is the first part of your answer. \n" ); document.write( "then you multiply (5m-3) * 3m \n" ); document.write( "answer is: \n" ); document.write( "(15m^2 - 9m) \n" ); document.write( "then you subtract (15m^2 - 9m) from (15m^2 + 11m - 12) \n" ); document.write( "answer is: \n" ); document.write( "(15m^2 + 11m - 12) - (15m^2 - 9m) = \n" ); document.write( "15m^2 + 11m - 12 - 15m^2 + 9m = \n" ); document.write( "(20m - 12) \n" ); document.write( "----- \n" ); document.write( "next you figure out how many times 5m goes into 20m. \n" ); document.write( "answer is: \n" ); document.write( "4 ********* this is the second part of your answer \n" ); document.write( "then you multiply (5m-3) * 4 \n" ); document.write( "answer is: \n" ); document.write( "(20m - 12) \n" ); document.write( "then you subtract (20m-12) from (20m - 12) \n" ); document.write( "answer is: \n" ); document.write( "20m - 12 - (20m - 12) = \n" ); document.write( "20m - 12 - 20m + 12 = \n" ); document.write( "0 \n" ); document.write( "----- \n" ); document.write( "your answer for (15m^2 + 11m - 12) / (5m-3) is (3m + 4) \n" ); document.write( "(3m+4) is the length. \n" ); document.write( "----- \n" ); document.write( "to prove your answer is correct, go back to the original equation of: \n" ); document.write( "A = L*W \n" ); document.write( "substitute for A, L, and W: \n" ); document.write( "15m^2 + 11m - 12 = (3m+4)*(5m-3) \n" ); document.write( "(3m+4)*(5m-3) = 15m^2 - 9m + 20m - 12 = \n" ); document.write( "15m^2 + 11m - 12. \n" ); document.write( "this is the same as the area you started with so the equation is true proving that the value of (3m+4) for the length is good. \n" ); document.write( "----- \n" ); document.write( "your answer is: \n" ); document.write( "length = (3m+4) \n" ); document.write( "----- \n" ); document.write( " \n" ); document.write( " |