How do you graph and label the vertex and axis of symmetry of $y=-(x-3)(x+1)$ ?

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Answer 1 · 2017-09-30T03:23:42

Vertex $(1,4)$
Axis of symmetry $x=1$

Given -

$y=-(x-3)(x+1)$

$y=(-x+3)(x+1)$
$y=-x^2+3x-x+3$
$y=-x^2+2x+3$

Vertex

$x=(-b)/(2a)=(-2)/(-2)=1$

At $x=1$

$y=-(1^2)+2(1)+3=-1+2+3=4$

Vertex $(1,4)$
Axis of symmetry $x=1$

Take a few values above and below $x=1$
Form a table, after finding the $y$ values.
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Graph it.
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How do you graph and label the vertex and axis of symmetry of y=-(x-3)(x+1)y=-(x-3)(x+1)?