Answer: y = 9sqrt(3)
"sqrt" is shorthand for "square root". If you need x as well, it is x = 18
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Step-by-step explanation:
This is a 30-60-90 triangle. The hypotenuse is twice that of the short leg, so the hypotenuse is x = 2*9 = 18 units.
The long leg is sqrt(3) times the short leg, so y = 9sqrt(3)
You could use the trig ratios (sine, cosine, tangent) to help find these values.