The greatest contributions were their writings that taught others how to achieve a simpler, less materialistic life.

a. transcendentalists
c. romantics
b. enlightenmentalists
d. all of the above

The Transcendentalists' greatest contributions were their writings that taught others how to achieve a simpler, less materialistic life.  

Explanation:

Transcendentalism was a spiritual and philosophical movement happening from the 1830s to the 1880s. This was one of the purest forms of Romanticism, in fact, it was inspired by it. This movement believed that humans could get to the truth by intuition and promoted the care of the inner self instead of the economic or material wealth.

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