Equation: S = $70·W + $550
Amount of manoey after 18 weeks: $1810
To solve this, we have two variables, the amount of weeks (W) and savings (S)
Each week, $70 dolars are added to the account. Then we can write this as: $70·W.
Now there is an initial amount of $550. Then we must add that mount to the previous calculation: $70·W + $550
This give us the savings on each week. THen THe complete equation is S = $70·W + $550
Now, to know the savings after 18 weeks, we can replace W = 18 and solve:
Thus, the savings after 18 weeks is $1810