Answer:
C
Step-by-step explanation:
Once

We know that 
There are infinity values for
, but considering 
Below we have all the solutions for 
Negative:

Positives:

We can see that 
Answer:
-3x^2 - 21x
Step-by-step explanation:
This question is representing multiplying two functions :
We are finding f(x) * g(x)
We know that f(x) is -3x and g(x) is x + 7, therefore :
(-3x)(x + 7)
Follow FOIL :
First :
(-3x)(x)
-3x^2
Outer :
(-3x)(7)
-21x
Therefore the answer is :
-3x^2 - 21x
773.77*0.5=386.88 hope i helped