SOLUTION: The graph of a quadratic function y = g(x) is shown and f(x) = 3x2 + bx + c. If the graph of g(x) is reflected over the y-axis then the new graph will have the same line of symmetr

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Question 1179006: The graph of a quadratic function y = g(x) is shown and f(x) = 3x2 + bx + c. If the graph of g(x) is reflected over the y-axis then the new graph will have the same line of symmetry as f(x). Find the value of "b" that makes this true. A) -3 B) -6 C) 3 D) 6
Found 2 solutions by greenestamps, ikleyn:
Answer by greenestamps(13200)   (Show Source): You can put this solution on YOUR website!


no graph of g(x) is shown
Answer by ikleyn(52803)   (Show Source): You can put this solution on YOUR website!
.

            It seems to me that I do understand your request.

            Look attentively for my steps. 


f(x) has the (vertical) axis of symmetry  x =  =  = .


It means that g(x) has the (vertical) axis of symmetry  x = .


Now, from your graph, you, the visitor,  SHOULD SEE  that axis of symmetry for g(x),

so you can restore the value of   first, and then the value of "b" itself.


In short terms,  the symmetry axis for  g(x)  is the mirror reflection of the symmetry axis of  f(x)  relative the  y-axis.


It means that  b-value for  g(x)  is the opposite number to the  b-value of  f(x).


That is all.  Quite obvious.


Solved,  answered and explained.



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