Answer:
See explanation
Step-by-step explanation:
Consider triangles PTS and QTR. In these triangles,
- given;
- given;
- as vertical angles when lines PR and SQ intersect.
Thus,
by AAS postulate.
Congruent triangles have congruent corresponding sides, so

Consider segments PR and QS:
![PR=PT+TR\ [\text{Segment addition postulate}]\\ \\QS=QT+TS\ [\text{Segment addition postulate}]\\ \\PT=QT\ [\text{Proven}]\\ \\ST=RT\ [\text{Given}]](https://tex.z-dn.net/?f=PR%3DPT%2BTR%5C%20%5B%5Ctext%7BSegment%20addition%20postulate%7D%5D%5C%5C%20%5C%5CQS%3DQT%2BTS%5C%20%5B%5Ctext%7BSegment%20addition%20postulate%7D%5D%5C%5C%20%5C%5CPT%3DQT%5C%20%5B%5Ctext%7BProven%7D%5D%5C%5C%20%5C%5CST%3DRT%5C%20%5B%5Ctext%7BGiven%7D%5D)
So,
![PR=SQ\ [\text{Substitution property}]](https://tex.z-dn.net/?f=PR%3DSQ%5C%20%5B%5Ctext%7BSubstitution%20property%7D%5D)
Answer:

Step-by-step explanation:
Your welcome
Answer:
Step-by-step explanation: 56776
I think the answer is 21. I’m not sure but if I remember it’s 40 + 20 = 60. 180 - 60 = 120 and then it’s a vertical angle which is equal so then it would be 120 + 39 = 159. Then 180 - 159 = 21. Sorry if this is wrong I haven’t done this in a while. Have a good day!