Question

Westley and Buttercup are each saving money. Westley starts with $85 in in his savings and add $5 per week (y=85+5x)

Buttercup starts with $10 in her savings account and adds $20 per week (y=10+20x)

After how many weeks will they have the same amount of money?

Answer 1

After 5 weeks.

Explanation:

Westley starts with $85 and saves $5 per week. So:

`y=85+5x`

Buttercup starts with $10 and saves $20 per week. So:

`y=10+20x`

When they have the same amount of money, the two equations will be equal to each other. Therefore:

`85+5x=10+20x`

Solve for x. Subtract 10 from both sides:

`75+5x=20x`

Subtract 5x from both sides:

`75=15x`

Divide both sides by 15:

`x=5`

Westley and Buttercup will have the same amount of money after 5 weeks.