Answer:
y = 1/2x + 0
Step-by-step explanation:
SOLUTION
From the question given the following statements to prove are correct, then the last part

The reason is Side-side-side triangle theorem
This theorem states that all three sides of a triangle are congruent (identical) to the corresponding sides of another triangle, then the triangles themselves are also congruent.
Hence the answer is Side-side-side triangle theorem
Compatible numbers are easy to divide mentally.
hope this helped