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)#