Answer :
Data:
after 8 weeks he deposits 280 (the same amount each week)
Then, in a week he deposits: $35
[tex]\frac{280}{8}=35[/tex]If you write an equation for y (total amount in the account) in terms of x (number of weeks you have the next:
[tex]y=35x[/tex]To find the number of weeks that will take to Anglelo to deposit 420 in total you substitute in the equation the y for 420 and solve the equation for x:
[tex]\begin{gathered} 420=35x \\ \\ x=\frac{420}{35} \\ \\ x=12 \end{gathered}[/tex]Then, Angelo will deposit in his account $420 in a total of 12 weeks (included the first 8 weeks when he deposits $280)