Answer:
a= -4
b=1
Explanation:
Midpoint=(1,-3)=(x,y)
A=(-6,-7)=(x1,y1)
Let ,the coordinates of B be 'a and b' .
So,
B=(a,b)=(x2,y2)
Using ,midpoint formula,
(x,y)=(x1+x2\2 , y1+y2 \2)
or, (1,-3)=(-6+a\2 , -7+b \2)
Now,
Taking the corresponding sides,
or, 1 =-6+a/2
or, 1*2=6+a
or, 2=6+a
or, 2-6=a
a=-4
Then,
-3= -7+b/2
or, -3*2= -7+b
or, -6 =-7+b
or, -6+7=b
b=1