Solve the following inequality.

(answers in attachment)

A -6 < x ≤ -3

Step-by-step explanation:

21 ≤ - 3(x - 4) < 30

Divide all parts by -3.  Remember that flips the inequalities

21/-3  ≥ - 3/-3 (x - 4) > 30/-3

-7  ≥  (x - 4) > -10

Add 4 to all sides

-7+4  ≥  x - 4+4 > -10+4

-3  ≥  x  > -6

Rearranging the order

-6 < x ≤ -3

x = ± 6i

step-by-step explanation:

x^2 = -36

take the square root of each side

sqrt(x^2) = sqrt(-36)

we know sqrt(ab) = sqrt(a) sqrt(b)

x = ±sqrt(36) sqrt(-1)

we know that sqrt (-1) = i

x = ± 6i