## Algebra 1: Common Core (15th Edition)

$y=x^2−8x−7$ The standard form for a quadratic equation is $y=ax^2+bx+c$ So a= 1, b= -8, and c= -7 Axis of symmetry: The formula for axis of symmetry is x=−b/2a x=−(−8)/2(1) x=8/2 x=4 Vertex: Plug in the x value of the axis of symmetry to find the y value of the vertex. $y=x^2−8x−7$ $y=(4)^2−8(4)−7$ y= 16 - 32 - 7 y= -23 The vertex is (4,-23)