To solve this, follow these steps:
5x + 27 = 9 (x+3) - 4x
Distribute the 9 within the parenthesis:
5x + 27 = 9x + 27 - 4x
Then combine like terms:
5x + 27 = 5x + 27
These two then cancel each other out completely.
This is an identity because an identity in math is when both equations equal each other, which is shown above.
Hope this helps!
Answer: 
Step-by-step explanation:





Answer:
x = 0, -4 and -3.
Step-by-step explanation:
The given expression is "3x to the power of 3 + 21x squared + 36x = 0".
We can write this expression as follows :

Taking 3x common.

x = 3

Hence, the solution of the given quadratic equation are x = 0, -4 and -3.