1 is in the 'Ten Thousand's' place.
Step-by-step explanation:

You're asking
(10⁶) times (10^p) = 10¹⁸ .
When you multiply two numbers that have the same base
but different exponents, you just add the exponents.
So 6 + p = 18
Subtract 6 from each side: p = 12 .
10⁶ x 10¹² = 10¹⁸ .
F(4-x)=12
Domain:(-oo,oo) these are infinity symbols by the way.
ANSWER X=4. You basically plug what y equals to into the second equation the solve for x.