Here are a few reasons:
The triangles have the same three sides
The triangles have the same three angles
The triangles could perfect overlap one another
They have corresponding angles.
Not sure if this helped but I hope so!
Answer:
The answer is 54
Step-by-step explanation:
If you follow PEMDAS, and x = 3, then you get 54. As an example, x4 is 12. You change X to 3, then multiply (3)4=12. If you follow the rest of the equation, you get 54.
-5=-2/9x.
x=22.5 / x=45/2