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**Monox D. I-Fly****Member**- From: Indonesia
- Registered: 2015-12-02
- Posts: 1,160

The reflection of the line 5x - 7y - 13 = 0 by the line y = -x is ....

A. 7x + 5y - 13 = 0

B. 7x + 5y + 13 = 0

C. 7x - 5y - 13 = 0

D. 7x - 5y + 13 = 0

E. 7y + 5x + 13 = 0

This one I totally have no idea. Like, at all.

Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away. May his adventurous soul rest in peace at heaven.

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**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,322

If you sketch the axes and the line of reflection you see that reflected points switch their x and y coordinates and reverse the signs eg (3,-4) becomes (4,-3)

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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