Which equation is equivalent to 3[x + 3(4x – 5)] = 15x – 24?

a.15x – 15 = 15x – 24
b.15x – 5 = 15x – 24
c.39x – 45 = 15x – 24
d.39x – 15 = 15x – 24
x

Given the original equation  3[x + 3(4x – 5)] = 15x – 24, only the left side of the equation needs simplifying. This is initially done by distributing 3 to x and 3(4x - 5), then simplifying further. This is shown below:

3[x + 3(4x – 5)] = 15x – 24
3x + 9(4x - 5) = 15x - 24

Distributing 9:
3x + 36x - 45 = 15x - 24

Simplifying:
39x - 45 = 15x - 24

The obtained form matches the answer from choice C.