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A parabola has the equation y = x2 - 10x + 28. What are the coordinates of its vertex?h Enter your answer in the box with parenthesis but no spaces in the form

User Gvee
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1 Answer

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12 votes

We have the parabola:


y=x^2-10x+28

There is one expression that gives you the x-coordinate of the vertex:


-(b)/(2a)

We know that the standard form of a quadratic function is: ax^2+bx+c, then:


-((-10))/(2(1))=(10)/(2)=5

Now, having x=5 we can substitute it on the original equation:


\begin{gathered} y=(5)^2-10(5)+28 \\ y=25-50+28 \\ y=3 \end{gathered}

The vertex of the parabola is (5, 3)

User Ljdyer
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