Yes, is subtraction, to get their "difference".
first off, let's convert the mixed fractions, to "improper", and then subtract.

Answer:
g(x)=(x+7)^2-3
Step-by-step explanation:
Given:
f(x)= x^2
Now we have to translate f(x) 7 units to the left and 3 units down to form the function g(x).
As per the rules of translation
when any parent function, in given case f(x)=x^2, is translated to 'a' units to the left then 'a' is added to the value of x. thus making f(x+a)
Also when the parent function is translated any 'a' units down then 'a' is subtracted from the value of function. thus making f(x)-a
Translating f(x), 7 units to the left
f(x+7)= (x+7)^2
Translating f(x+7), 3 units down
f(x+7)-3 = (x+7)^2-3
Hence new function g(x)=(x+7)^2-3!
Answer:
The second one
Step-by-step explanation:
If you need the sum than here is an equation for it 7x3= 21
This is a square, and so all the sides will be the same measurements. Note that you are given an area, so you'll have to root the total area to get a side.
√400 = 20
One side's measurements is 20 in
hope this helps