Positive real numbers x and y satisfy y^{3}=x^{2} and (y-x)^{2}=4 y^{2}. What is x+y?

**Answer Choices**

A. 12

B. 18

C. 24

D. 36

E. 42

Positive real numbers x and y satisfy y^{3}=x^{2} and (y-x)^{2}=4 y^{2}. What is x+y?

**Answer Choices**

A. 12

B. 18

C. 24

D. 36

E. 42