The best definition for the term substitution would be...
the action of replacing someone or something with another person or thing.
Answer:
and 
Step-by-step explanation:
We must solve the quadratic equation to find the values of x that satisfy equality

Subtract 24 on both sides of equality


Now we factor the quadratic equation
Identify two numbers that when you add them you get as a result 2 and when you multiply them you get as a result -24
The numbers sought are: 6 and -4
So the factors are:

Finally note that the solutions are:
and 
That he is keeping track who he owes money to and when he has to do it
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