document.write( "Question 1128435: The height of a triangle is 3 inches less than 5 times the length of its base. The area is 34 square inches. Find the length of the base and the height of the triangle. \n" ); document.write( "
Algebra.Com's Answer #744898 by rothauserc(4718)\"\" \"About 
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area(A) of a triangle = (1/2) * base * height
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\n" ); document.write( "let b be the triangle's base, then
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\n" ); document.write( "height = 5b -3
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\n" ); document.write( "(1/2) * b * (5b-3) = 84
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\n" ); document.write( "multiply both sies of = by 2
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\n" ); document.write( "b * (5b-3) = 168
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\n" ); document.write( "5b^2 -3b = 168
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\n" ); document.write( "5b^2 -3b -168 = 0
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\n" ); document.write( "use the quadratic formula
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\n" ); document.write( "x = (-b + or - square root(b^2 - 4 * a * c))/(2*a)
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\n" ); document.write( "b = (-(-3) +square root((-3)^2 -4*5*(-168)))/(2*5) = 6.1043
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\n" ); document.write( "b = (-(-3) -square root((-3)^2 -4*5*(-168)))/(2*5) = -5.5043
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\n" ); document.write( "we reject the negative value for the base
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\n" ); document.write( "base is approximately 6.1 inches and height is 27.5 inches
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\n" ); document.write( "(1/2) * 6.1 * 27.5 = 83.875 is approximately 84 square inches
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