[tex]y=ax^2+bx+c\\\\y=a(x-h)^2+k\ where\ h=\dfrac{-b}{2a};\ k=f(h)=\dfrac{-(b^2-4ac)}{4a}[tex]y=-3x^2+7x-5\\\\a=-3;\ b=7;\ c=-5\\\\h=\dfrac{-7}{2\cdot(-3)}=\dfrac{7}{6}\\\\k=\dfrac{-(7^2-4\cdot(-3)\cdot(-5)}{4\cdot(-3)}=\dfrac{-49+60}{-12}=-\dfrac{11}{12}\\\\y=-3\left(x-\dfrac{7}{6}\right)^2-\dfrac{11}{12}[/tex]
