Foil:
First term
Outer term
Inner term
Last term
By using foil we just times the first terms together so: x*x=x^2
Then we times the outer terms together so: x*9=9x
Then we times the inner terms together so:7*x=7x
Finally we times the last terms together so: 7*9=63
So our equation is:
X^2+9x+7x+63
Now we collect the like terms
Answer: x^2+16x+63
Hope this helped