Using a system of equations, it is found that the simplified equation is y = 6x - 5.
Last year, Ada was x - 1 years old and Bill was y - 1 years old.
Bill was 6 times as old as Ada, hence:
[tex]y - 1 = 6(x - 1)[/tex]
[tex]y - 1 = 6x - 6[/tex]
[tex]y = 6x - 6 + 1[/tex]
[tex]y = 6x - 5[/tex]
The simplified equation is y = 6x - 5.
For a similar problem, also involving a system of equations, you can check https://brainly.com/question/13773803