Question

Determine as coordenas do vértice da função $y=- x^{2} +6x-9$

Answer 1

-x²+6x-9=0
∆=b²-4ac
∆=6²-4.(-1).(-9)
∆=36-36
∆=0
xv=-b/2a
xv=-6/2.(-1)
xv=-6/-2
xv=3
yv=-∆/4a
yv=-0/4.(-1)
yv=-0/-4
yv=0
(3, 0)