Answer:
![9c^3 - 12c^2 - 18c - 24= [3c^2 - 6][3c - 4]](https://tex.z-dn.net/?f=9c%5E3%20-%2012c%5E2%20-%2018c%20-%2024%3D%20%5B3c%5E2%20-%206%5D%5B3c%20-%204%5D)
Step-by-step explanation:
Given

Required
Factor
Group into 2
![[9c^3 - 12c^2] - [18c + 24]](https://tex.z-dn.net/?f=%5B9c%5E3%20-%2012c%5E2%5D%20-%20%5B18c%20%2B%2024%5D)
Factorize each group
![3c^2[3c - 4] - 6[3c - 4]](https://tex.z-dn.net/?f=3c%5E2%5B3c%20-%204%5D%20-%206%5B3c%20-%204%5D)
Factor out 3c - 4
![[3c^2 - 6][3c - 4]](https://tex.z-dn.net/?f=%5B3c%5E2%20-%206%5D%5B3c%20-%204%5D)
Hence:
![9c^3 - 12c^2 - 18c - 24= [3c^2 - 6][3c - 4]](https://tex.z-dn.net/?f=9c%5E3%20-%2012c%5E2%20-%2018c%20-%2024%3D%20%5B3c%5E2%20-%206%5D%5B3c%20-%204%5D)
so x=5
substituting for x in the equation we get:

Ans C: 16
And the question is......................
Double the first equation: 4x+14y=-2 and subtract the second: 17y=17, so y=1. 2x=-7y-1=-7-1=-8, so x=-8/2=-4.
The answer is x=-4 and y=1.