\[\boxed{\text{288\ (288).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[y = 4x^{2};\text{\ \ }A\ (a;16):\]
\[4x^{2} = 16\]
\[x^{2} = 4\]
\[x = 2 \rightarrow \ \ a = 2;\]
\[x = - 2 \rightarrow \ \ a = - 2.\]
\[Ответ:a = \pm 2.\ \ \]