Determine the Constant of Variation for the Stated Condition $y$ Varies Directly as the Square Of

Multiple Choice

Determine the constant of variation for the stated condition.
-If $y$ varies directly as the square of $x$ , and $y = 540$ when $x = 15$ , find $y$ when $x = 10$ .

A) 240
B) 360
C) 1215
D) 810