Question

if p(-1 1) is the midpoint of the line segment joining a(-3,6) & b(1,b+4),then find the value of b

Answer 1

use section formula of midpoint ,
let (a, b) and (r, s ) are given two points
then midpoint of these ={(a+r)/2, (b+s)/2}

now,
p (-1,1) is the midpoint of A and B
for y co-ordinate of p
1=(6+b+4)/2

2=b+10

b=-8

Answer 2

B will be equal to 8 ...