You can use a tangent:

We have opposite = 17 and adjacent = x.

substitute:
cross multiply
multiply both sides by √3

divide both sides by 3

Use the Pythagorean theorem:

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Other method.
triangle.
The sides are in the ratio 
Therefore

1 second = 1.5 meters
t second = 1.5t meters
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Answer: d = 1.5t
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Answer:
The answer is 49
Step-by-step explanation:
the square = 10×4= 40
The triangle = 6×3= 18 >> 18÷2 = 9ft
40+9= 49ft