Algebra-1

Question Analysis
This question tests the student's ability to use the substitution method to solve a system of linear equations. The first equation is already in the form , which can be directly substituted into the second equation.

Key Concept Explanation
The substitution method involves expressing one variable in terms of the other using one of the equations, then substituting this expression into the other equation to eliminate one variable and solve for the other.

Step-by-step Solution
1. The first equation is already in the form .
2. Substitute into the second equation: .
3. Simplify the equation: .
4. Subtract 5 from both sides: