Question

Leon needs to save more than $350 to buy a new bike. He has$130 saved so far, and he plans to save $20 each week until he has enough. The inequality below represents x, the number of weeks he must save to have the extra money needed. Which best describes the number of weeks he must save before he can buy his bike?

Answer 1

$350= $130+$20x, x= amount of weeks
$350-$130=$220 $20*11=220
Answer: 11 weeks

Answer 2

Leon needs $350
Leon has $130
Leon wants to save $20 per week
x = weeks

First, let's place what Leon needs on the left side of the equation:

$350 = ...

We know Leon as $130 saved so far, he plans to save $20 a week.
So, what you do here is add $130 to $20x. The reason why x is next to the $20 is because Leon wants to save $20 a week (the x represents the week). The reason why you add 130 is that's what Leon has saved so far. Therefore, the right side of your equation should look like this:

... = 130 + 20x

whereas 130 represents the amount saved so far, 20 represents weekly savings, x represents the number of weeks.

Put the left and right sides of the equation together and you should have:

$350 = $130 + $20x

Now, if you want to solve the equation:

Subtract 130 from both sides

  350 =  130 + 20x
- 130   - 130
-----------------------------
220 = 20x

Then, divide 20 by both sides

220 = 20x
-----   -----
20      20

11 = x

Leon needs to save up $20 for 11 weeks if he wants to buy the bike.

Want to check your answer?

Plug in 11 for x since 11 is the number of weeks.

350 = 130 + 20(11)
350 = 130 + 220
350 = 350

Answers match, therefore your answer is correct