Answer: 5 small rooms and 10 large rooms.
Step-by-step explanation:
Let be "s" the number of small rooms reserved and "l" the number of large rooms reserved.
Using the information given in the exercise, set up a System of equations:
[tex]\left \{ {{3s+5l=65} \atop {l=2s}} \right.[/tex]
Now, in order to solve the System of equations, you can use the Substitution method. The steps are:
1. You must substitute the second equation into the first equation:
[tex]3s+5l=65\\\\3s+5(2s)=65[/tex]
2. Now, you must solve for the variable "s" in order to find its value:
[tex]3s+5(2s)=65\\\\3s+10s=65\\\\13s=65\\\\s=5[/tex]
3. Finally, substitute the value of "s" into the second equation and evaluate, in order to find the value of "l". You get that this is:
[tex]l=2s\\\\l=2(5)\\\\l=10[/tex]