ANSWER:
STEP-BY-STEP EXPLANATION:
With the information in the statement we can propose the following system of equations: Let x be the ticket value for students and y value the ticket for adults.
[tex]\begin{gathered} 15x+10y=145\text{ (1)} \\ 21x+14y=203\text{ (2)} \end{gathered}[/tex]Solving x in (1)
[tex]\begin{gathered} 15x=145-10y \\ x=\frac{145}{15}-\frac{10}{15}y \\ x=\frac{29}{3}-\frac{2}{3}y\text{ (3)} \end{gathered}[/tex]Replacing (3) in (2):
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