Many real world scenarios can be modeled using systems of equations. In fact, when we have two quantities that
are related and two ways in which those quantities are related, then we can often set up and solve a system.
Exercise #1: Jonathan has nine bills in his wallet that are all either five-dollar bills or ten-dollar bills.
(a) Fill out the following table to see the (b) If f represents the number of $5 bills and t dependence of the two
variables and how they represents the number of $10 bills, then what then determine how much money
Jonathan has. does the following expression calculate? Explain.
Number
of fives, f
0
Number
of tens, t
Amount of Money. S
PAT
b) If f represents the number of $5 bills and t represents the
number of $10 bills, then what does the following
expression calculate? Explain. 5f+ 10t
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TE
TOT