4n-9=15. N=6 (n stands for number)
-6(4x + 1) + 7x + 9(x - 3) = 4
-6(4x) - 6(1) + 7x + 9(x) - 9(3) = 4
-24x - 6 + 7x + 9x - 27 = 4
-24x + 7x + 9x - 6 + 27 = 4
-8x + 21 = 4
- 21 - 21
-8x = -17
-8 -8
x = 2.125
Answer:
I'm pretty sure its b but I'm not sure I'm sorry if it's wrong