document.write( "Question 1069760: A room is one yard longer than it is wide. At 75c per sq. yd. a covering for
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document.write( "the floor costs S31.50. Find the dimensions of the floor.
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Algebra.Com's Answer #684883 by addingup(3677)![]() ![]() You can put this solution on YOUR website! (W+1)*W*0.75 = 31.50 \n" ); document.write( "Are they asking you to solve using the quadratic formula or completing the squares? I'll complete the squares, the answer is the same either way you calculate it: \n" ); document.write( "Rewrite: \n" ); document.write( "3/4W(W+1) = 31.50 multiply both sides times 4/3: \n" ); document.write( "W(W+1) = 42.00 Distributive Properties of multiplication: \n" ); document.write( "W^2+W = 42 \n" ); document.write( "Now we have to complete the squares. This is a mechanical process, it's the same every time: \n" ); document.write( "Take one-half of the coefficient of x and square it, then add it to both sides: \n" ); document.write( "The coefficient of W is 1 (W = 1W, and 1 is the coefficient). Half of 1 is 1/2 and 1/2^2 = 1/2*1/2 = 1/4 Add 1/4 to both sides: \n" ); document.write( "W^2+W+1/4 = 169/4 \n" ); document.write( "Factor the left side: \n" ); document.write( "(W+1/2)^2 = 169/4 take the square root of both sides to get rid of the exponent \n" ); document.write( "W+1/2 = 13/2 \n" ); document.write( "Because it's a quadratic equation, we get two possible answers: \n" ); document.write( ": \n" ); document.write( "W = 13/2-1/2 or W = -13/2-1/2 \n" ); document.write( "W = 6 or W = -7 \n" ); document.write( "We are not looking for a negative number, so throw away the -7 and try the 6: \n" ); document.write( ": \n" ); document.write( "(W+1)*W*0.75 = 31.50 \n" ); document.write( "(6+1)*6*0.75 = 31.50 \n" ); document.write( "7*6*0.75 = 31.50 Because of the properties of multiplication, you can multiply in any order you like. I'll go with 7*6 because I can do it in my head: \n" ); document.write( "42*0.75 = 31.5 Multiply 42*0.75 and see what you get ;-) \n" ); document.write( ": \n" ); document.write( "Happy learning, \n" ); document.write( "John \n" ); document.write( " \n" ); document.write( " |