Chapter 5 Polynomials and Polynomial Functions - 5.1 Use Properties of Exponents - 5.1 Exercises - Mixed Review - Page 335: 58

See the graph

$y=-2x^2-1$ The function is already in quadratic standard form $y=ax^2+bx+c$ with $a=-2, b=0, c=-1$. Find the x-coordinate: $x=-\frac{b}{2a}=-\frac{0}{2.(-2)}=0$ Substitute for x: $y=-2(0)^2-1 \rightarrow y=-1$ The vertex is $(0,-1)$. Also the axis of symmetry is $x=0$. Find some other points: $x=-1 \rightarrow y=-3$ $x=1 \rightarrow y=-3$ $x=-2 \rightarrow y=-9$ $x=2 \rightarrow y=-9$