Answer:

Step-by-step explanation:
First, recall the 4 basic imaginary exponents:

So, we want to find:

This is the same as:

52 is 4 times 13. Thus:

Since we know that i to the fourth is 1:

Simplify:

And this equals:

So:

It would be 70*35 / 100 + 30*25 / 100
2450 /100 + 750/100
24.50 + 7.50 = 32
So, your answer is $32
The answer is 3.785, but rounding it to the nearest hundredth is 3.78 or 3.79, depending on rather they wanted you to take the 5 and round up or just leave it off.
I'd suggest using "elimination by addition and subtraction" here, altho' there are other approaches (such as matrices, substitution, etc.).
Note that if you add the 3rd equation to the second, the x terms cancel out, and you are left with the system
- y + 3z = -2
y + z = -2
-----------------
4z = -4, so z = -1.
Next, multiply the 3rd equation by 2: You'll get -2x + 2y + 2z = -2.
Add this result to the first equation. The 2x terms will cancel, leaving you with the system
2y + 2z = -2
y + z = 4
This would be a good time to subst. -1 for z. We then get:
-2y - 2 = -2. Then y must be 0. y = 0.
Now subst. -1 for z and 0 for y in any of the original equations.
For example, x - (-1) + 3(0) = -2, so x + 1 = -2, or x = -3.
Then a tentative solution is (-3, -1, 0).
It's very important that you ensure that this satisfies all 3 of the originale quations.