how was the war on the frontier during the American revolution different from the rest of the fighting in the war?

When the Revolutionary War began, many of the tribes in the Ohio Valley took it as an ... Other tribes hoped to remain neutral, a difficult position when sandwiched ... Amid raids launched by the British from Detroit and others from hostile tribes, ... fought in what became the state of Kentucky during the Revolutionary War

the answer is a) to be able to obey them.

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