Explain because i have to show my work please and thank you

Answer:
D.) [tex]y=19.99x+30[/tex]
Step-by-step explanation:
x represents the hours. The magician charges $19.99 per hour. "Per" means multiplication, so:
[tex]19.99*x[/tex]
[tex]19.99x[/tex]
adding the travel and miscellaneous expense:
[tex]19.99x+30[/tex]
This represents the total charge, represented by y:
[tex]y=19.99x+30[/tex]
:Done