It shows three periods of a sin graph
We know that
the quadratic function in vertex form is--------------> y=a*(x-h)²+k
we have
f(x)=x²<span>+14x+40
y=</span>x²+14x+40
We can convert to vertex form by completing the
square on the right hand side
y-40=x²+14x
y-40-49=x²+14x-49------> subtract 49 on BOTH sides to
preserve the equality
y-40=(x²+14x+49)-49
y=(x²+14x+49)-49+40---------> y=(x+7)²-9
the answer is
the quadratic function in vertex form-----------> y=(x+7)²-9
<span>the vertex is the point (-7,-9)
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