geometry (please explain)

Question

Look at the figure shown below:

Nora is writing statements as shown below to prove that if segment ST is parallel to segment RQ, then x = 45:

StatementReason
1.	Segment ST is parallel to segment RQ.	Given
2.	Angle QRS is congruent to angle TSP.	Corresponding angles formed by parallel lines and their transversal are congruent.
3.	Angle SPT is congruent to angle RPQ.	Reflexive property of angles
4.	Triangle SPT is similar to triangle RPQ.	Angle-Angle Similarity Postulate
5.	?	Corresponding sides of similar triangles are in proportion.

Which equation can she use as statement 5?

Answer 1

5. PS / PT = SR / TQ OR PS / SR = PT / TQ

I DID THIS ONE:

PS=60 PT = 48 SR = X TQ = 36

60 / 48 = X / 36

48 * X = 60 * 36

48 X = 2160

48 / 48 X = 2160 / 48

X = 45