Answer:
1. x=160 (here given as ques no. 5)
2. x=81 (here given as ques no.5)
4. No (here given as ques no. 8)
Step-by-step explanation:
1. Given ∠STR=∠SRT=20°
we know ∠STR+∠STU=180
x+20=180
x=160
2. By external angle property
x+24=105
x=81
3. By Angle Sum Property
∠ 1=∠2=∠3=∠4=90
and
∠5=∠6=∠7=∠8=90
Hence all angles are equal to 90
and we know only parallel lines have
∠4=∠5
∠3=∠6
hence line 'r' and line 't' are parallel.
4. For being parallel side pieces must not form a triangle(i.e. sum two interior angle must be equal to 180)
But here sum of interior angle 174
Hence a triangle is possible.
So , lines are not possible .