SOLUTION: A triangle has a height of 6cm and a base of 8 cm. If the height and the base are both decreased by the same amount, the area of the new triangle is 20 cm squared. what is the base

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height 6 cm
base 8 cm
decreased by x cm
6-x & 8-x will be the new height and base
Arae of triangle = 1/2 *(6-x)(8-x)=20
(6-x)(8-x)=20*2
48-14x+x^2=40
x^2-14x +8=0
use quadratic formula
discriminant = 164
x1= (14+sqrt164)/2
x1=(14+12.8)/2
=26.8/2
23.4 ( not possible)
x2= 14-sqrt164)/2
x2=14-12.8)/2
x2=1.2/2
x2=0.6 cm
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The new dimensions are height = 5.4, base = 7.4
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