Find the vertex of y=-(x-1)(x+4)?

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Answer 1 · 2018-07-09T05:50:02

Vertex #(-3/2, 25/4)#

Given -

#y=-(x-1)(x+4)#

#y=-(x^2-x+4x-4)#

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

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

#x=(-b)/(2a)=(-(-3))/(2 xx -1)=3/(-2)=-3/2#

At #x=-3/2; y=-(-3/2)^2-3(-3/2)+4#

#y=-9/4+9/2+4=(-9+18+16)/4=25/4#

Vertex #(-3/2, 25/4)#

Answer 2 · 2018-07-09T12:06:48

#(3/2, 25/4)#

#y=-(x-1)*(x+4)#

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

#y=-x^2-3x-(3/2)^2+4+(3/2)^2#

#y=25/4-(x-3/2)^2#

Hence vertex of this equation is #(3/2, 25/4)#