Which of the following might be considered a valid source for online research? select all that apply.

the phoenicians, based on a narrow coastal strip of the levant, put their excellent seafaring skills to good use and created a network of colonies and trade centres across the ancient mediterranean. their major trade routes were by sea to the greek islands, across southern europe, down the atlantic coast of africa, and up to ancient britain. in addition, arabia and india were reached via the red sea, and vast areas of western asia were connected to the homeland via land routes where goods were transported by caravan. by the 9th century bce, the phoenicians had established themselves as one of the greatest trading powers in the ancient world.

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