1. D (Equilangiler, whatever you spell it)
2. A (Obtuse)
3. B (Right Triangle)
<span>ΔABC, ΔDEF, and ΔGHI
</span>
I think all triangles are congruent. 2 sides and 1 angle of each triangle is has the same measure. Making these triangles congruent in SAS theorem.
Given the triangles ABC and EDC
We will find the transformation that makes the triangles are similar
As shown: the triangles are reflected over the y-axis
the rule of the reflection over the y-axis will be as follows:

And as shown, the length of the side AB = 3 units
And the length of the side ED = 1 units
So,

So, the answer will be:
D) (x,y) ⇒ (-x, y)
E) (x,y) ⇒ (1/3 x, 1/3 y)