Your diagram looks correct.

Your x-values appear to be correct.

Edit: My initial values were:

30, 30

120, 30

75, 107

25, 69

89, 5

112, 92

Here are my values for all six points:

55.9606 93.2372

120.0000 30.0000

33.8773 6.8293

25.0000 69.0000

115.5079 69.5705

70.7442 -8.4950

MATLAB plots the 0,0 origin at left,bottom corner. The figure is flipped to match yours.

Here is the MATLAB code using matrix arithmetic:

Your x-values appear to be correct.

Edit: My initial values were:

30, 30

120, 30

75, 107

25, 69

89, 5

112, 92

Here are my values for all six points:

55.9606 93.2372

120.0000 30.0000

33.8773 6.8293

25.0000 69.0000

115.5079 69.5705

70.7442 -8.4950

MATLAB plots the 0,0 origin at left,bottom corner. The figure is flipped to match yours.

Here is the MATLAB code using matrix arithmetic:

Code:

```
% 2017.04.28 - MrChips
% define points of two triangles p and q
p1 = [ 30 30];
p2 = [120 30];
p3 = [ 75 107];
q1 = [ 25 69];
q2 = [ 89 5];
q3 = [112 92];
p = [p1;p2;p3];
q = [q1;q2;q3];
all = [p;q]; % all points
% shift
[nrows, ncols] = size(all);
Shift = ones(nrows,1) * q1;
all = -Shift + all;
% rotate
a = atan((p2(2)-q1(2))/(p2(1)-q1(1)));
Rotate = [[cos(a) -sin(a)]; [sin(a) cos(a)]];
all = all * Rotate;
% reflect about p2-q1 line
Reflect = ones(nrows,2);
Reflect(:,2) = -Reflect(:,2);
all = Reflect .* all;
% rotate back
a = -a;
Rotate = [[cos(a) -sin(a)]; [sin(a) cos(a)]];
all = all * Rotate;
% shift back
all = Shift + all
```

Last edited: