You can put this solution on YOUR website! Let the length of the triangle be x.
width= x + 8
area= x * (x+8)
=x(x+8)
=x^2 + 8x
280=x^2 + 8x
x^2 + 8x - 280= 0 <====quadratic equation
{{x = (-8 +- sqrt( b^2-4*1*-280 ))/(2*1) }}
x=-4(+/-)2sqrt(74)
x=13.2 (nearest decimal place)
or
x=-21.2
The width can't be a negative because you can't have a negative width.
Therefore, the width is 13.2 to the nearest decimal place.
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