Help me please, i don't know how to figure it out, its compound intrest

Maria walks a round trip of 0.75 mile to school every day.how many miles will she walk in 4.5 days

Adoctor administers a drug to a 38-kg patient, using a dosage formula of 50 mg/kg/day. assume that the drug is available in a 100 mg per 5 ml suspension or in 500 mg tablets. a. how many tablets should a 38-kg patient take every four hours? b. the suspension with a drop factor of 10 ggt/ml delivers the drug intravenously to the patient over a twelve-hour period. what flow rate should be used in units of ggt/hr? a. the patient should take nothing pills every four hours. (type an integer or decimal rounded to the nearest hundredth as needed.)

Which steps could be part of the process in algebraically solving the system of equations, y+5x=x^2+10 and y=4x-10