Answer: Robert has 22 video games.
Step-by-step explanation:
Let be "r" the number of video games that Robert has and "s" the the number of video games that Samuel has.
Set up a system of equations:
[tex]\left \{ {{r=5s+7} \atop {r+s=25}} \right.[/tex]
You can use the substitution method to solve the system:
- You need to substitute the first equation into the second equation and solve for "s":
[tex](5s+7)+s=25\\\\6s=25-7\\\\s=\frac{18}{6}\\\\s=3[/tex]
- Finally you must substitute the value of "s" into the first equation and evaluate:
[tex]r=5(3)+7\\\\r=22[/tex]
