Question

If the endpoints of AB have the coordinates A(9, 8) and B(-1, -2), what is the midpoint of AB?

Answer 1

Answer:
D. (4,3)

Explanation:
The endpoints of the line are given as (9,8) and (-1,-2)
1- Computing the x-coordinate of the midpoint:
Xmidpoint = (x1+x2) / 2 = (9+-1)/2 = 8/2 = 4
2- Computing the y-coordinate of the midpoint:
Ymidpoint = (y1+y2) / 2 = (8+-2) / 2 = 6/2 = 3

Based on the above, the midpoint is (4,3)

Hope this helps :)

Answer 2

$\bf ~~~~~~~~~~~~\textit{middle point of 2 points }\\\\ \begin{array}{ccccccccc} &&x_1&&y_1&&x_2&&y_2\\ % (a,b) &A&(~ 9 &,& 8~) % (c,d) &B&(~ -1 &,& -2~) \end{array}\qquad % coordinates of midpoint \left(\cfrac{ x_2 + x_1}{2}\quad ,\quad \cfrac{ y_2 + y_1}{2} \right) \\\\\\ \left( \cfrac{-1+9}{2}~~,~~\cfrac{-2+8}{2} \right)\implies \left( \cfrac{8}{2}~~,~~\cfrac{6}{2} \right)\implies (4~~,~~3)$