<PRE><B>Question 196019</B>
Area  =  Length * Width
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BUT,,L= 3w-6,,,, given
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A=l*w = (3w-6) * w = 3w^2 -6w = 45,,,given
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3w^2 -6w -45  =0
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3 (w^2 -2w -15) +0
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Factoring
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3(w+3)(w-5) = 0
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using  Zero  Property
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w+3 =0,,,,w = -3,,,not   realistic
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W-5 = 0,  w=5,,,,ANSWER
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Checking
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w=5, L=3w-6 =3*5-6 = 15-6=9
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A = l*w = 9*5 = 45 ,,,ok
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