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What is the image of (-3,-7) after a reflection over the x-axis?

User ProNeticas
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1 Answer

10 votes

Answer:

(-7,-3)

y=-x=-3

x=-y=-7

Explanation:

Or if you like you can find the equation for the line perpendicular to y=-x that goes through (3,7). Slope is the negative inverse of -1 which is +1. equation is y-7=x-3 or y=x+4

set x+4 = -x to get the point where the two lines intersect. x=-2, then y= 2 that's the point (-2,2)

Now you want to go the same distance on the other side of y=-x to get the image of (3.7)

(-2,2) is just (3-5,7-5) Just subtract 5 from each coordinate. Now subtract another 5 to get

(-2-5, 2-5) = (-7,-3)

short cut is just switch the 3 and 7 and change the sign of both to get (07,-3)

User Jessicardo
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