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4 votes
Which point is the vertex of the quadratic function f(x)=x2−6x+8?

User VNO
by
6.1k points

2 Answers

1 vote

Another method!

Pvertex→(x,y)(4,9)

Step-by-step explanation:

Given: y=x2−8x+7

This is already in the form y=a(x2+ba)+c as a=1

So we can do this 'trick'

Applying x vertex=(−12)(ba)(−12)(−8)=+4

To determine yvertex

Substitute for x=(−4) in the original equation giving:

yvertex=(4)2−8(4)+7

y vertex=+16−32+7=−9

User Wolfgang Kuehn
by
6.2k points
7 votes
(3,-1)
It needs to be written in standard form before you try to solve it.

User East Of Nowhere
by
5.4k points