SOLUTION: Find the x-intercepts, y-intercepts and the vertex of g(x)=-3x^2+6x+1

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Question 460960: Find the x-intercepts, y-intercepts and the vertex of g(x)=-3x^2+6x+1
Answer by lwsshak3(11628) About Me  (Show Source):
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Find the x-intercepts, y-intercepts and the vertex of g(x)=-3x^2+6x+1
..
g(x)=-3x^2+6x+1
2nd degree equations are parabolas and the standard form for parabolas is: y=A(x-h)^2+k with (h,k) being the (x,y) coordinates of the vertex. A is a multiplier which affects the steepness of the curve.
completing the square
y=-3(x^2-2x+1)+1+3
y=-3(x-1)^2+4
Vertex:(1,4)
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y-intercept
x=0
y=1
..
x-intercept
y=0=-3(x-1)^2+4
-3(x-1)^2=-4
(x-1)^2=-4/-3=4/3
x-1=√4/√3=2/√3
x=1±2/√3=1±1.1547
x=2.1547
or
x=.1547
see graph below as a visual check on the answers
+graph%28+300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C-3x%5E2%2B6x%2B1%29+