Answer:
[tex]x=60^{\circ}[/tex]
Step-by-step explanation:
The angle formed by [tex]48+x[/tex] and the angle marked as [tex]72^{\circ}[/tex] are co-interior angles and therefore must be supplementary (add up to 180 degrees).
Therefore, we have:
[tex]48+x+72=180,\\x+120=180,\\x=\boxed{60^{\circ}}[/tex]
