Its a geometry question i do not understand.

Check out the attached image. Since the two angles PQS and SQR are adjacent and form angle PQR, this means we simply add up the angles

(Angle PQR) = (Angle PQS) + (Angle SQR)

Angle PQR = 87 + 33

Angle PQR = 120 degrees

in geometry, parallel lines are lines in a plane which do not meet; that is, two lines in a plane that do not intersect or touch each other at any point are said to be parallel. by extension, a line and a plane, or two planes, in three-dimensional euclidean space that do not share a point are said to be parallel.