for geometry:(
please help, will give brainist
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Step-by-step explanation:
Given A( 1 , -2)=( x1, y1)
B( x2 , y2)
Mid point of AB, M ( -2 , 1)
Now we have the formula for the mid point that is
Mid point of AB = [ (x1 + x2)/ 2 , ( y1 + y2) /2]
Or, ( -2 , 1 ) = [ ( 1 + x2) / 2 , ( -2 + y2) / 2]
Now equating with the corresponding elements we get,
-2 = ( 1 + x2) / 2
-4 = 1 + x2
x2 = -4 - 1
x2 = -5
Also
1 =( -2 + y2) / 2
2 = -2 + y2
y2 = 2+2
y2 = 4
Therefore the coordinates of B are ( -5 , 4)
Hope it helps. :)