Answer:

Step-by-step explanation:
The midpoint of two points is the average of the x coordinates and the average of the y coordinates.
Given
A(3, -1)
and we let the other end point B be B(x,y)
and midpoint is (-7,10)
So, the average of 3 and x is -7, and
the average of -1 and y is 10
We can solve for x first:

and now solving for y:

So, the other point B is:

The answers would be 11, if you plug it in it would be 5(11)-7=48
substitution and elimination means that you need to use one equation and substitute it in place of some variable in the other equation.
Consider the above two equations.
Take equation 1, which is 4x-2y=22 => x=(22+2y)/4
substitute the x value gained above in equation 2.
so, 2((22+2y)/4)+4y=6
22+2y+8y=12 => 10y = -10 => y= -1.
Substitute y= -1 in x value obtained in the beginning.
So, x= (22 - 2)/4 => 5.
There fore, x= 5 and y= -1
Hope it helps.
Answer:
Sorry, I can't type well.