SOLUTION: how do you find the vertex for y=-xsquared+8x-3

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Question 975416: how do you find the vertex for y=-xsquared+8x-3
Found 2 solutions by Boreal, Shana-D:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
y=x^+8x-3
vertex x-value is -b/2a, and that is -8/2=-4
y(-4)=16-32-3=-19
(-4,-19)
graph%28300%2C200%2C-10%2C10%2C-30%2C50%2Cx%5E2%2B8x-3%29

Answer by Shana-D(6) About Me  (Show Source):
You can put this solution on YOUR website!
y = -x^2 + 8x - 3
use x = -b/(2a) to find x at the vertex.
plug this value back into the equation to find y at the vertex.
x = -b/(2a)
x = -8/(2*-1)
x = 4
now plug 4 back in: y = -(4)^2 + 8(4) - 3
Vertex is at (4, 13)