What is the the vertex of y = x^2-4x+20 ?

1 Answer
Jun 18, 2018

"vertex "=(2,16)

Explanation:

"given a parabola in "color(blue)"standard form ";ax^2+bx+c

"then the x-coordinate of the vertex is"

•color(white)(x)x_(color(red)"vertex")=-b/(2a)

x^2-4x+20" is in standard form"

"with "a=1,b=-4" and "c=20

x_("vertex")=-(-4)/2=2

"substitute this value into the equation for y-coordinate"

y_("vertex")=2^2-4(2)+20=16

color(magenta)"vertex "=(2,16)