We can solve this equation by completing the square. Notice that

and

. Therefore, we can turn

into

. y, in this equation, only has one real solution: 4. So your answer would be (B).
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The equation for a trapezoid is A = a+b all over 2 times h
So, you would simply substitute.
A=15
B=12
H=8
15+12/2 (8)=
27/2 (8)=
13.5 (8)=
108.
Proportional:
82.8 / 92 = 0.9
73.8 / 82 = 0.9
so
FG / 47 = 0.9
FG = 47 * 0.9
FG = 42.3
answer
The distance between 2 campsites is 42.3 m.