We know that the 8 represent the squared radius of the circle so to get the radius we should take the square root of 8
the answer is √8 = 2√2
3 and 2/3 hours.
Multiply the number of hours Dominic spent by the scale factor.
The first triangle has a perimeter of 4+6+10 = 20.
The 2nd longest side is 6/20 = 3/10 of the perimeter. In the larger triangle, the 2nd longest side will have length (3/10)*60 = 18.
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These side lengths mean the "triangle" is a line segment. That is, it has zero area.