What makes supply needed or wanted

The law of demand says that at higher prices, buyers will demand less of an economic good. The law of supply says that at higher prices, sellers will supply more of an economic good. These two laws interact to determine the actual market prices and volume of goods that are traded on a market.

Explanation:

the growing interconnectedness of the world through communication, trade, and the exchange of ideas is an important theme in the history of the 20th and 21st centuries.

explanation:

8 - (2a + 7) = a + 40     distribute/multiply - into (2a + 7)

8 - 2a - 7 = a + 40

1 - 2a = a + 40       add 2a on both sides

1 = 3a + 40         subtract 40 on both sides

-39 = 3a       divide 3 on both sides

-13 = a

[proof]

8 - (2a + 7) = a + 40

8 - (2(-13) + 7) = -13 + 40

8 - (-26 + 7) = 27

8 - (-19) = 27

8 + 19 = 27

27 = 27