alright lets crush this other base here
$${\mathtt{4}}{\mathtt{\,\times\,}}{{\mathtt{x}}}^{{\mathtt{2}}}{\mathtt{\,-\,}}{\mathtt{72}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{225}} = {\mathtt{0}}$$
first lets simplify x
$${\mathtt{4}}{\mathtt{\,\times\,}}{{\mathtt{x}}}^{{\mathtt{2}}} = {\mathtt{4}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,\times\,}}{\mathtt{4}}{\mathtt{\,\times\,}}{\mathtt{x}} = {\mathtt{16}}{\mathtt{\,\times\,}}{\mathtt{x}}$$
$${\mathtt{16}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{72}}{\mathtt{\,\times\,}}{\mathtt{x}} = {\mathtt{\,-\,}}\left({\mathtt{56}}{\mathtt{\,\times\,}}{\mathtt{x}}\right)$$
now its:
$${\mathtt{\,-\,}}{\mathtt{56}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{225}} = {\mathtt{0}}$$
add 225 to both sides:
$${\mathtt{\,-\,}}\left({\mathtt{56}}{\mathtt{\,\times\,}}{\mathtt{x}}\right) = {\mathtt{225}}$$
divide 56 both sides:
$${\mathtt{\,-\,}}{\mathtt{x}} = -{\mathtt{4.017\: \!857\: \!142\: \!857\: \!142\: \!9}}$$
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