SOLUTION: the line with the equation y= 2x + 3 is reflected in the y-axis. find the equation of the image line
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-> SOLUTION: the line with the equation y= 2x + 3 is reflected in the y-axis. find the equation of the image line
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Question 919973: the line with the equation y= 2x + 3 is reflected in the y-axis. find the equation of the image line Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website! when the equation is reflected about the y-axis.
(x,y) becomes (-x,y)
you get the same y value that is the same distance from the y-axis but on opposite sides of it.
in f(x) terms, this means that f(x) is equal to f(-x)
your original equation is y = 2x + 3
replace x with (-x) an dyou get y = 2 * -x + 3 which becomes y = -2x + 3.
that's your reflected equation.
the graph of both equations will show you that the equations are symmetric about the y-axis.
this means that x = 3 becomes y = 2x + 3 which becomes y = 9 in the original equation.
this means that x = -3 becomes y = -2x + 3 which becomes y = 9 in the reflected equation.
the graphs looks like this:
a horizontal line has been placed at y = 9 so you can see that, when y = 9, x = 3 or -3.
