Question 1128435
area(A) of a triangle = (1/2) * base * height
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let b be the triangle's base, then
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height = 5b -3
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(1/2) * b * (5b-3) = 84
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multiply both sies of = by 2
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b * (5b-3) = 168
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5b^2 -3b = 168
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5b^2 -3b -168 = 0
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use the quadratic formula
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x = (-b + or - square root(b^2 - 4 * a * c))/(2*a)
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b = (-(-3) +square root((-3)^2 -4*5*(-168)))/(2*5) = 6.1043
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b = (-(-3) -square root((-3)^2 -4*5*(-168)))/(2*5) = -5.5043
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we reject the negative value for the base
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base is approximately 6.1 inches and height is 27.5 inches
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(1/2) * 6.1 * 27.5 = 83.875 is approximately 84 square inches
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answer checks
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