Two less than 2 times a number is the same as the number plus 64. What is the number?

66

Explanation:

2x-2=x+64

2x-2=64+2

x=66

(b) britain had a much larger navy than the u.s.

(d) the u.s. had a small army compared to britain.

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