For this case we have that by definition it is fulfilled:

Where:
a: It is the base
b: It is the exponent
So, if we have the following expression:
-6 to the power of 4, is equivalent to: 
So we have to:
-6: It is the base
4: It is the exponent
Answer:
-6: It is the base
4: It is the exponent
First thing you should do is reduce coefficients.
1st equation has all multiples of '2'. Divide by 2
---> x +3y = -6
2nd equation has multiples of 5. Divide by 5.
---> x - y = 2
Now elimination part is easier.
Eliminate 'x' variable by subtracting 2nd equation from 1st.
x + 3y = -6
-(x - y = 2)
----------------------
4y = -8
Solve for 'y'
4y = -8
y = (-8)/4 = -2
Substitute value for 'y' back into 2nd equation:
x - (-2) = 2
x + 2 = 2
x = 0
Solution to system is:
x=0, y =-2
Answer: Definition of Vertical Angles.

Length of each side of each of these three equilateral triangle is :
Solution is in attachment ~
Answer:
1. cell?
2. distinction
3. assumption
4. foliage
5. commission
6. dimension
7. considerable
8. membrane
9. cell
10. final
11. viewpoint
12. considerable
Step-by-step explanation: