Poll taxes and literacy tests were established to limit the voting rights of a: poor white southerners. b: people in border states. c: african american men. d: african american women.

The correct answer is C. Poll taxes and literacy tests were established to limit the voting rights of African American men.

Explanation:

Poll taxes and literacy tests were required before to vote in some parts of the United States, which resulted in the restriction to the right of suffrage of less wealthy or less educated people, that is, African-American workers.

simplify brackets

8 - 2a - 7 = a + 40

simplify 8 - 2a - 7 to -2a + 1

-2a + 1 = a + 40

add 2a to both sides

1 = a + 40 + 2a

simplify a + 40 + 2a to 3a + 40

1 = 3a + 40

subtract 40 from both sides

1 - 40 = 3a

simplify 1 - 40 o -39

-39 = 3a

divide both sides by 3

-39/3 = a

simplify 39/3 to 13

-13 = a

switch sides

a = -13