Bisects means to separate in equal parts, meaning each part is equal. This means the equations on each side of the line are equal. Once you equate them, you combine like terms finding your answer.
1) 2x+ 3=x+7
-x -x
x+3 = 7
-3 -3
Answer: x=4 (do this for the others)
2) x=7/2
3) x=5/2
Answer:
The other end point is: s+ti = 3+9i
Step-by-step explanation:
Mid-Point(M) in the complex plane states that the midpoint of the line segment joining two complex numbers a+bi and s+ti is the average of the numbers at the endpoints.
It is given by: 
Given: The midpoint = -1 + i and the segment has an endpoint at -5 - 7i
Find the other endpoints.
Let a + bi = -5 -7i and let other endpoint s + ti (i represents imaginary )
Here, a = -5 and b = -7 to find s and t.
then;
[Apply Mid-point formula]
On comparing both sides
we get;
and 
To solve for s:
or
-2 = -5+s
Add 5 to both side we have;
-2+5 = -5+s+5
Simplify:
3 = s or
s =3
Now, to solve for t;

2 =-7+t
Add 7 to both sides we get;
2+7 = -7+t+7
Simplify:
9 = t
or
t =9
Therefore, the other end point (s+ti) is, 3+9i
Answer:
20 mm
Step-by-step explanation:

T × 1/4 which equals 7/8
T = 7/8 × 4 which equals 7/2
7/2 is your answer