For this case, the first thing we must do is define variables.
We have:
x: number of quarters
y: number of half dollars
We write the system of equations that adapts to the problem.
We have then:
[tex]x = 3y
0.25x + 0.5y = 13.75[/tex]
Solving the system of equations graphically, we have:
[tex]x = 33
y = 11[/tex]
(see attached image for graphic solution)
The amount of coins you have is:
[tex]x + y = 33 + 11 = 44
[/tex]
Answer:
He has 44 coins in total
