Thank you for the answer but I need it broken down as if I was explaining this whole system of equation problem to an audience.

Thank you for the answer but I need it broken down as if I was explaining this whole system of equation problem to an audience. Meaning like the first sentence starting with Let x = or Let L=    And the second sentence starting with Let y = or Let W=  to the end of getting the answer. Also can you please let me know what method you used (Solved by Substitution or Elimination) Thank you