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Find B and C so that y=1x^2 +bx+c has vertex (3,8)B=_____C=____What is it asking?I am so confused

User DotnetShadow
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1 Answer

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Quadratic Function

The general form of a quadratic equation is:


y=ax^2+bx+c

Comparing this equation with the given function:


y=1x^2+bx+c

It's clear that

a=1

We don't know the values of b and c.

To find them, we use the vertex form of the quadratic equation:


y=a\mleft(x-h\mright)^2+k

Where the point (h,k) are the coordinates of the vertex.

Substituting the coordinates of the vertex (3,8):


y=a(x-3)^2+8

Expanding the square and substituting a=1:


y=x^2-6x+9+8=x^2-6x+17

The equation is now in standard form, and we can easily identify the values of b and c:

b = -6

c = 17

User James Choi
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