Which is the other endpoint of a line segment with one endpoint at [tex]$(-2,5)$[/tex] and midpoint at [tex]$(3,1)$[/tex]?

A. [tex]$\left(\frac{1}{2}, 3\right)$[/tex]
B. [tex]$(1,6)$[/tex]
C. [tex]$\left(\frac{5}{2},-2\right)$[/tex]
D. [tex]$(5,-4)$[/tex]
E. [tex]$(8,-3)$[/tex]



Answer :

To determine the coordinates of the other endpoint of a line segment when one endpoint and the midpoint are given, we can utilize the midpoint formula. The midpoint formula states that the coordinates of the midpoint [tex]\((xm, ym)\)[/tex] of a line segment with endpoints [tex]\((x1, y1)\)[/tex] and [tex]\((x2, y2)\)[/tex] are given by:

[tex]\[ xm = \frac{x1 + x2}{2}, \quad ym = \frac{y1 + y2}{2} \][/tex]

We are given:
- One endpoint [tex]\((x1, y1) = (-2, 5)\)[/tex]
- The midpoint [tex]\((xm, ym) = (3, 1)\)[/tex]

We need to find the coordinates of the other endpoint [tex]\((x2, y2)\)[/tex].

### Step-by-Step Solution

1. Express the midpoint coordinates in terms of the endpoints:
[tex]\[ xm = \frac{x1 + x2}{2}, \quad ym = \frac{y1 + y2}{2} \][/tex]

2. Substitute the known coordinates of the midpoint and one endpoint into the equations:
[tex]\[ 3 = \frac{-2 + x2}{2}, \quad 1 = \frac{5 + y2}{2} \][/tex]

3. Solve for [tex]\(x2\)[/tex]:
[tex]\[ 3 = \frac{-2 + x2}{2} \][/tex]
Multiply both sides by 2:
[tex]\[ 6 = -2 + x2 \][/tex]
Add 2 to both sides:
[tex]\[ 8 = x2 \][/tex]
So, [tex]\(x2 = 8\)[/tex].

4. Solve for [tex]\(y2\)[/tex]:
[tex]\[ 1 = \frac{5 + y2}{2} \][/tex]
Multiply both sides by 2:
[tex]\[ 2 = 5 + y2 \][/tex]
Subtract 5 from both sides:
[tex]\[ -3 = y2 \][/tex]
So, [tex]\(y2 = -3\)[/tex].

5. Thus, the coordinates of the other endpoint are:
[tex]\[ (x2, y2) = (8, -3) \][/tex]

After verifying our work with the calculations, the correct answer is:

[tex]\[ \boxed{(8, -3)} \][/tex]

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