[tex]f(x) = -7x^2 + 3x + 1 \\ \\a=-7, \ b=3 , \ c=1 \\ \\ vertex(h, k) \ is \ given \ by: \\ \\ h = \frac{-b}{2a } , \ \ k = c-\frac{b^2}{4a} \\ \\h=\frac{-3}{2\cdot (-7)}=\frac{-3}{-14}=\frac{3}{14}[/tex]
[tex]k = 1-\frac{ 3^2}{4 \cdot (-7)} =1-\frac{9}{-28}=1+\frac{9}{28}=1\frac{9}{28}=\frac{37}{28}\\ \\ \\ Answer : \ Vertex =(\frac{3}{14}, \frac{37}{28})[/tex]
