Question

Elena has $240 in the bank. She withdraws $15 each week to pay for piano lessons. How many lessons can she afford with her savings? Let L equal the number of lessons.

Answer 1

15L= 240

1) The way to tackle this question is by modeling an equation for that.

2) Notice that $240 is the initial value she has. We don't know the number of weeks. But we know the more lessons she has the less money she will have, for she is paying from her savings.

So we can write out the following function:

`C(L)=240-15L`

3) Let's rewrite it as an equation Plugging C(w) = 0

`\begin{gathered} 240-15L=0 \\ -15L=-240 \\ (-15L)/(-15)=(-240)/(-15) \\ L=16 \\ \end{gathered}`

4) Examining the answer we can state that the answer is 15L= 240 note that when we divide both sides by 15, we get the answer L=16.