MID-POINT 3

Find a if the midpoint of a line from (a, 4) to (5, 10) is (7, 7)

Solution

x1=a, x2=5, y1=4, y2=10.

(7, 7)= (x1 + x2, y1 + y2)

                2             2

(7, 7)= (a + 5,  4 + 10)

               2          2

(7, 7)= (a + 5, 14)

               2      2

Equating values of x;

7= a + 5

        2      

2 x 7= (a + 5)  x 2 ¹

              2 ₁     

14 = a + 5

14-5 = a

a = 9.

Hence a=9

TRY THIS……………………..

Find m if the midpoint of a line from (m, 12) to (5, 10) is (7, 11)