## cassidyohrt Group Title Find the coordinates of the point (-5,7) when it is reflected across the line y=11. one year ago one year ago

1. punnus

Use mid point formula.

2. cassidyohrt

But don't you need more than one coordinate?

3. punnus

mirror being mid point of the line joining the two points. $\left\{ -5,11 \right\}$ now $-5=\frac{x2-x1 }{ 2 }$ and $11=\frac{ y2-y1 }{ 2 }$

4. punnus

you know x1 and y1 find x2 and y2

5. punnus

Did you get it .

6. cassidyohrt

I completely understand what you're saying, but I honestly have no idea how to solve for x2 and y2. I remember learning this, but I haven't used it in 2 years.

7. punnus

did you get the idea behind mid point

8. cassidyohrt

Yes I do!

9. punnus

Then take the given point as the first point in the case i.e (-5,7)

10. punnus

now use x1=-5 and y1=7

11. punnus

now use the formula that I have already posted

12. cassidyohrt

Wait, so wouldn't it be (-5,-7)?

13. cassidyohrt

Nevermind, let me resolve quick.

14. punnus

did you get is answer as (-5,15). If not I can give us an another approach