$$\begin{aligned}
& x ^ { 3 } - 2 y = 7 \\
& x ^ { 4 } - 2 x y = 21
\end{aligned}$$ Given this, what is $\mathbf { x }$? A) 3 B) 5 C) 7 D) 9 E) 11
$$\begin{aligned}
& x ^ { 3 } - 2 y = 7 \\
& x ^ { 4 } - 2 x y = 21
\end{aligned}$$
Given this, what is $\mathbf { x }$?\\
A) 3\\
B) 5\\
C) 7\\
D) 9\\
E) 11