What is the vertex form of $y = x^{2} - 5 x + 4$ $y= x^2 - 5x + 4$ ?

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Answer 1 · 2016-02-26T10:41:09

Vertex form ${(x - \frac{5}{2})}^{2} = y - - \frac{9}{4}$ $(x-5/2)^2=y--9/4$

from the given $y = x^{2} - 5 x + 4$ $y=x^2-5x+4$
we complete the square

$y = x^{2} - 5 x + \frac{25}{4} - \frac{25}{4} + 4$ $y=x^2-5x+25/4-25/4+4$

$y = (x^{2} - 5 x + \frac{25}{4}) - \frac{25}{4} + \frac{16}{4}$ $y=(x^2-5x+25/4)-25/4+16/4$

$y = {(x - \frac{5}{2})}^{2} - \frac{9}{4}$ $y=(x-5/2)^2-9/4$

$y + \frac{9}{4} = {(x - \frac{5}{2})}^{2}$ $y+9/4=(x-5/2)^2$

also

${(x - \frac{5}{2})}^{2} = y - - \frac{9}{4}$ $(x-5/2)^2=y--9/4$

graph{y=x^2-5x+4[-20,20,-10,10]}

have a nice day!

What is the vertex form of y= x^2 - 5x + 4 y=x2−5x+4y= x^2 - 5x + 4 ?