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HELP ME PLZZZZZZZZZZZZZZ

HELP ME PLZZZZZZZZZZZZZZ-example-1

1 Answer

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Given:

The quadratic equation is


y=3x^2-18x+15

To find:

The x-coordinate and y-coordinate of the vertex.

Solution:

If a quadratic function is defined by
f(x)=ax^2+bx+c, then the vertex is defined as:


Vertex=\left((-b)/(2a),f((-b)/(2a))\right)

If
a<0, then the function has a maximum at the vertex and ff
a>0, then the function has a minimum at the vertex.

We have,


y=3x^2-18x+15

Here,
a=3,b=-18,c=15.

Since
a=3>0, therefore the function has a minimum at the vertex. So, fill min in first blank.

Now,


(-b)/(2a)=(-(-18))/(2(3))


(-b)/(2a)=(18)/(6)


(-b)/(2a)=3

Putting x=3 in the given function, we get


y=3(3)^2-18(3)+15


y=27-54+15


y=-12

Therefore, the vertex is at point (3,-12).

User Ugurcan Yildirim
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