## anonymous one year ago Write the quadratic function in vertex form. y = x2 - 2x + 5

1. anonymous

first coordinate of the vertex of \$$y=ax^2+bx+c$$ is always $-\frac{b}{2a}$

2. anonymous

second coordinate of the vertex is what you get for $$y$$ when you replace $$x$$ by the first coordinate

3. anonymous

once you have the vertex $$(h,k)$$ then vertex form is $y=a(x-h)^2+k$ in your case $$a=1,b=-2$$

4. anonymous

5. anonymous

y=(x+1)^2-4?

6. anonymous

oh no

7. anonymous

8. anonymous

$-\frac{b}{2a}=-\frac{-2}{2\times (-1)}=1$

9. anonymous

if you replace $$x$$ by $$1$$ you get $$4$$ not $$-4$$

10. anonymous

so $y=(x-1)^2+4$

11. anonymous

Thanks!

12. anonymous

yw