What is the vertex of # y= –x^2 +12x – 4?

1 Answer
Mar 23, 2016

color(blue)("Vertex"->(x,y)->(6,32)Vertex(x,y)(6,32)

Explanation:

color(blue)("General condition")General condition

Consider the standard form of y=ax^2+bx+c)y=ax2+bx+c)

Write this as y=a(x^2+b/ax)+cy=a(x2+bax)+c

x_("vertex")=(-1/2)xxb/axvertex=(12)×ba
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(blue)("Solving your question")Solving your question

In your case a= -1 and b=12 ->x_("vertex")=(-1/2)xx12/(-1) = +6a=1andb=12xvertex=(12)×121=+6

Substitute x=6 -> y_("vertex")=32x=6yvertex=32

color(blue)("Vertex"->(x,y)->(6,32))Vertex(x,y)(6,32)

Tony B