The sum of these will simply be the sum of all the numbers 1 through 26, which is 351.
Answer:
(-1, 5)
Step-by-step explanation:
3 [x + y = 4]
3x + 3y = 12
- 3x + 7y = 32
-4y = -20
y = 5
x + 5 = 4
x = -1
I think it’s the fourth one!!
Given problem is 
To simplify that we need to multiply and divide by conjugate of the denominator
conjugate of denominator 6+i will be 6-i as we just need to change sign of the imaginary part
Now multiply and divide by 6-i







Hence final answer is 
You can describe the domain by every possible x value in the function, since that function has a vertical intersection line which means the x value will never pass it on the negative side, the domain would be from -2 to all the postive numbers, X > -2 or (-2,∞).
For the range, simply it's all the possible y values. In that function it's impossible to go under 0 or negative value. That means the range would be Y>0 or (0,∞).
If you want to know if it's a function or not you could try the vertical line test, select any x value and draw straight line on it, if the line crosses 2 y points in the same x value it wont be a function, In your case each x value has it's own Y value.
So the answer is Domain x>-2; Range y>0; Yes, it is a function