## sierra14 Group Title determine the vertex and the axis of symmetry for the function Y=-x^2+2x+1 3 years ago 3 years ago

1. sierra14 Group Title

$Y=-x^2+2x+1$

2. Chandman Group Title

Can Somebody help me please D:

3. satellite73 Group Title

same magic formula as before. use $\frac{-b}{2a}$ for the first coordinate of the vertex. second coordinate is what you get when you plug it in

4. satellite73 Group Title

in this case a = -1, b = 2 so $-\frac{b}{2a}=-\frac{2}{2\times(-1)}=1$

5. satellite73 Group Title

plug in 1 for x and you win. i get -1+2+1=2 so vertex is (1,2)