Answer:
[tex](25,-71)[/tex]
Step-by-step explanation:
Given
[tex](x,y) = (19,5)[/tex] --- midpoint
[tex](x_1,y_1) = (13,81)[/tex] --- end 1
Required
The other endpoint
Using midpoint formula, we have:
[tex](x,y) = 0.5 * [x_1 + x_2, y_1 + y_2][/tex]
So, we have:
[tex](19,5) = 0.5 * [13 + x_2, 81 + y_2][/tex]
Multiply both sides by 2
[tex]2 * (19,5) = 2 * 0.5 * [13 + x_2, 81 + y_2][/tex]
[tex](38,10) = [13 + x_2, 81 + y_2][/tex]
By comparison:
[tex]x_2 + 13 = 38[/tex] and [tex]y_2 + 81 = 10[/tex]
So:
[tex]x_2 = 38 - 13[/tex]
[tex]x_2 = 25[/tex]
and
[tex]y_2 = 10 - 81[/tex]
[tex]y_2 = - 71[/tex]
Henc, the other endpoint is:
[tex](25,-71)[/tex]