As there are 81 tiles total, that makes your area 81. Being a square, that makes your area equation A=s^2. As you need a side, this makes your equation s=√A. Plugging in 81 as A, we get s=√81=9, so an edge has 9 tiles.
The answer is 42.
The question is asking for angle N. We know from the question that angle N is equal to angle E (Don't think about the scale factor because it only applies to the sides. They're just trying to trick you).
To find angle E:

Move numbers to the right side:

Combine like terms:

Divide both sides by 13:

The formula for angle E:

Plug in the 8:

The angle measure of E is 42. So angle N is automatically 42 too.
To solidify, we can try to use the formula which they give us for angle N:
Answer:
Cual es la forma más simple al efectuar la operación indicada en la expresión (-3) (-12) ? this means What is the simplest way to perform the operation indicated in the expression (-3) (-12)?
Step-by-step explanation:
Multiply -3 by -12 and get 36. hope this was helpful.