Answer:
x = 48°
Step-by-step explanation:
Complementary angles
Angles that sum to 90°.
Vertical Angle Theorem
When two straight lines intersect, the vertical angles are congruent (equal).
Therefore, angle x is equal to the angle that is complementary to 42°.
To find x, subtract 42° from 90°:
⇒ x = 90° - 42°
⇒ x = 48°