Final answer:
To solve the system of equations by substitution, solve one equation for one variable and substitute it into the other equation. Start by solving the first equation for y and substitute the expression into the second equation. Simplify the equation to find the value of x, and then substitute it back to find the value of y.
Step-by-step explanation:
To solve the system of equations by substitution, we will solve one equation for one variable and substitute it into the other equation. Let's start with the first equation, 2y = 6x + 10. Solving for y gives us y = 3x + 5. Now we can substitute this expression for y in the second equation, 3x - ly = 5.
Substituting y = 3x + 5, we get 3x - l(3x + 5) = 5. Expanding the brackets gives us 3x - 3lx - 5l = 5. Simplifying the equation, we have (3 - 3l)x - 5l = 5. Now we have a single-variable equation, which we can solve to find the value of x. Once we find x, we can substitute it back into y = 3x + 5 to find the value of y.