Answer
It is possible to find f(x+7) by replacing each occurrence of
X by X+7
Answer:
x+y=4+8=12
$12 for one of each
or if you mean indivually (the wording confused me)
$4 for child, $8 for adult
Step-by-step explanation:
x=adult
y=child
2x+10y=56
4x+5y=52
iin order to be able to subtract values and find x and y im going to multiply 4x+5y=52 by two and get 8x+10y=104
8x+10y=104
-2x+10y=56
6x=48 divide each side by 6
x=8
plug 8 back into an equation to find cost of y
2(8)+10y=56
-16 -16
10y=40
y=4
You know
Squaring both sides gives
Then raising both sides to any integer power 
gives
That is, any power of 
where the power is a multiple of 4 will always be equal to 1.
So
But perhaps you mean to write 20+1 as the exponent, in which case
Jenny does, she bakes 12 for every x and dan bakes 10 for every x.
So in conclusion jenny bakes more cookies per batch
