document.write( "Question 704340: Can someone please help me understand this question? I would like to know the process of how you come to the answers as I have a test tomorrow!
\n" ); document.write( "y=-2(x-3)^2+8
\n" ); document.write( "a)State the coordinates of the vertex
\n" ); document.write( "b)State whether is has a max or min value and what that is?
\n" ); document.write( "c)State the equation of the axis of symmetry
\n" ); document.write( "d)State the y-intercept.
\n" ); document.write( "If you could show me how you reach each answer..that would be amazing!
\n" ); document.write( "Thank you
\n" ); document.write( "

Algebra.Com's Answer #434055 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
y=-2(x-3)^2+8
\n" ); document.write( "a)State the coordinates of the vertex
\n" ); document.write( "You have to remember the \"vertex form\" of a quadratic:
\n" ); document.write( "y = a(x-h)^2 + k
\n" ); document.write( "where (h,k) is the vertex
\n" ); document.write( "since your equation was:
\n" ); document.write( "y=-2(x-3)^2+8
\n" ); document.write( "we immediately can see that the vertex is at:
\n" ); document.write( "(h,k) = (3,8)
\n" ); document.write( "b)State whether is has a max or min value and what that is?
\n" ); document.write( "We can tell by the \"coefficient\" associated with the x^2 term:
\n" ); document.write( "y=-2(x-3)^2+8
\n" ); document.write( "expanding the above:
\n" ); document.write( "y=-2(x^2-6x+9)+8
\n" ); document.write( "y=-2x^2+12x-18+8
\n" ); document.write( "y=-2x^2+12x-10
\n" ); document.write( "Since it will be \"negative\" -- we conclude that it will be a parabola that opens downwards. Thus the vertex will be the MAX.
\n" ); document.write( "Note: do part c first, then come back to this
\n" ); document.write( "c)State the equation of the axis of symmetry
\n" ); document.write( "axis of symmetry is at:
\n" ); document.write( "x = -b/(2a)
\n" ); document.write( "x = -12/(2(-2))
\n" ); document.write( "x = -12/(-4)
\n" ); document.write( "x = 3 (axis of symmetry)
\n" ); document.write( "d)State the y-intercept.
\n" ); document.write( "set x to zero:
\n" ); document.write( "y=-2x^2+12x-10
\n" ); document.write( "y=-2(0)^2+12(0)-10
\n" ); document.write( "y=0+0-10
\n" ); document.write( "y = -10
\n" ); document.write( "y-intercept is at (0, -10)
\n" ); document.write( "
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