Answer:
D(4) = 6
Step-by-step explanation:
Using the blue graph, find the y value when x =4
the y value is 6 when x=4
D(4) = 6

it is true; just work them out, you should get what they got :))
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

Answer:
- 15
Step-by-step explanation:
