What did Martin Luther King, Jr. do right after the arrest of Rosa Parks? A
He organized a march on Washington, DC.
B
He went on a pilgrimage to Mecca.
C He delivered his "I Have a Dream" speech.
D
He organized a bus boycott in Montgomery, Alabama.

D

Explanation:

The successful Montgomery Bus Boycott, organized by a young Baptist minister named Martin Luther King, Jr., followed Park's historic act of civil disobedience.

i believe the answer is c

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