Why do scientists belive the first inhabitants crossed the land bridge

 As early as the 1500s, early settlers and European thinkers were ... One theory suggested the migration of Norsemen across Greenland ... It wasn't until the mid-1920s that scientists would finally restart the search for evidence of how people ... Some scientists believed the land bridge contained uniformed .

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

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