[tex]\text{Acompanhe.}\\\\ \text{Seja } f(x)=-2x^{2}+16x-7=-2(x-4)^{2}+25.\\\\ \text{Ent\~ao, }\sup\limits_{x \in R}f(x)=25 \iff x=4.\\\\ \text{Assim, as coordenadas do v\'ertice de } f(x) \text{ s\~ao } (4, \, 25).\\\\ \text{Bons estudos, ma dear.}[/tex]
