What is the axis of symmetry and vertex for the graph #y = x ^2 - 4 x + 3#?

2 Answers
May 26, 2017

Vertex #(2, -1)#
Axis of symmetry #x=2#

Explanation:

Given -

#y=x^2-4x+3#

Vertex -
x-coordinate of the vertex

#x=(-b).(2a)=(-(-4))/(2xx1)=4/2=2#

y-coordinate of the vertex

#y=2^2-4(2)+3=4-8+3=-1#

Vertex #(2, -1)#

Axis of symmetry #x=2#

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May 26, 2017

#X=2#

#(2,-1)#

Explanation:

Another way of finding the axis and vertex is to complete the square

#y=x^2-4x+3#

#y=(x-2)^2-1#

for the vertex find the #x" "# value that makes the bracket #=0#

#x=2=>y=-1#

vertex #(2,-1)#

axis of symmetry simply the the x-value above #X=2#

with the graph as before