Help solve this pls and thanks !!!

Answer:
just add the x's then you will get it that how i got to do it
Step-by-step explanation:
Answer: The answer is this c=6x^2-3x-11
Step-by-step explanation:
c=P-a-b:
P=10x^2+4x-9
a=7x+3
b=4x^2-1
c=10x^2+4x-9-(7x+3)-(4x^2-1)
Refine
c=6x^2-3x-11 <---This is the answer