Answer:
10
Step-by-step explanation:
Use the distance formula.

We have x1 = 2; y1 = 0; x2 = -6; y2 = 6.





Answer: 10
X+y+z=22
(x+y+z+t)/4=8
subsitute
x+y+z=22
(22+t)/4=8
multiplly by 4
22+t=32
subtract 22
t=10
the fourth number is 10
We can plug those values into the equation, and if the answer is incorrect, we'll know if either one is extraneous.
√11 - 2(-7) = √(-7)^2 + 4(-7) + 4
√25 = √25
5 = 5
The first solution, -7, makes the equation true, and so it is not extraneous.
√11 - 2(1) = √(1)^2 + 4(1) + 4
√9 = √9
3 = 3
The second solution, 1, makes the equation true, and so it is also not extraneous.
<h3>The correct option is D, neither solution is extraneous. </h3>