What is the the vertex of #y = x^2-4x+20 #?
1 Answer
Jun 18, 2018
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)#
