Level Balance Pans

In the picture

1. 1Badge 1 sits on a cloth pouch in the left pan.
2. 2Badge 2 sits on the cloth pouch in the right pan.
3. 3Badge 3 sits on a wooden cube in the left pan.
4. 4Badge 4 sits on a wooden cube in the right pan.

Examples

• Two friends sharing marbles by removing the same number from each hand.
• A see-saw staying level when equal weights are added to or removed from both sides.

Quiz: Level Balance Pans (Age 14)

1. 1

   What rule must you follow when solving an equation with a balance model?

   • Do an operation only to the side with the unknown.
   • Do the same operation to both sides.
   • Move numbers to the other side without keeping the sides balanced.
2. 2

   In the equation 2x + 2 = x + 4, which operation best moves toward isolating x?

   • Add x and 2 to both sides.
   • Subtract x and 2 from both sides.
   • Subtract 2 from the left side and add 2 to the right side.
3. 3

   Why is it allowed to remove identical amounts from both sides of a balanced equation?

   • Because removing equal amounts from equal sides keeps the sides equal.
   • Because removing items always makes the unknown smaller.
   • Because only the left side needs to match the right side at the end.

The answers, each with its explanation, are in the app. This lesson has left the free week, so its quiz is part of the subscription.