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How do you find the vertex when the equation is written in graphing form?
Graphing Form: y=(x-2.5)^2+0.75
Vertex: (2.5,0.75)
Let's complete the square. To do that, we will consider the variable terms on the function's right-hand side. y= x^2-5x+7 To visualize how we complete the square, we draw a generic rectangle where the upper left corner has an area of x^2 and the adjacent rectangles each have an area that is half that of -5x.
Since the upper left corner has an area of x^2, it must be a square with a side length of x. This allows us to factor the adjacent rectangle's areas to - 2.5* x. With this information, we can also determine the area of the lower right rectangle which completes the square.
a(- b)=- a * b
(- a)^2=a^2
a^2-2ab+b^2=(a-b)^2
Calculate power
LHS-6.25=RHS-6.25