MHB [ASK] Reflection of a Line by Another Line

  • Thread starter Thread starter Monoxdifly
  • Start date Start date
  • Tags Tags
    Line Reflection
Click For Summary
The discussion focuses on finding the reflection of the line 5x - 7y - 13 = 0 across the line y = -x. Participants explore substituting y = -x and x = -y into the original line equation. The correct reflection is determined to be 7x + 5y - 13 = 0. The contributor expresses surprise at the complexity of this problem compared to others. The conversation highlights the importance of understanding line reflections in geometry.
Monoxdifly
MHB
Messages
288
Reaction score
0
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.
 
Mathematics news on Phys.org
If we let:

$$y=-x$$

and

$$x=-y$$

in the given line, what do we obtain?
 
-5y + 7x - 13 = 0?
 
Monoxdifly said:
-5y + 7x - 13 = 0?

Correct. :)
 
I can't believe that out of the 4 questions I asked tonight, the one I found the hardest was the one with the simplest step.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 7 ·
Replies
7
Views
1K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
28
Views
4K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 7 ·
Replies
7
Views
2K