How do you check your work after finding x

The jurassic zoo charges $14 for each adult admission and $5 for each child. the total bill for 77 people from a school trip was $565. how many adults and how many children went to the zoo? i

The parabola x= √y-9 opens: a.)up b.)down c.)right d.)left

Lines a and b are parallel. what is the value of x? -5 -10 -35 -55