Question

Manuel wants to save $600 to buy a TV. He saves 18 each week. The amount A (in dollars) that he still needs after w weeks is given by the following function.A (w) = 600-18w

Answer 1

(a) Substituting with w = 7 into the equation we get:

`\begin{gathered} A(7)=600-18\cdot7 \\ A(7)=600-126 \\ A(7)=474 \end{gathered}`

He still needs $474

(b) Substituting with A(w) = 294 into the equation we get:

`\begin{gathered} 294=600-18w \\ 294-600=-18w \\ -306=-18w \\ (-306)/(-18)=w \\ 17=w \end{gathered}`

He has been saving for 17 weeks.