hi
Distance between two point is given by application of following formula
V ( ( X2-X1)² ) + (Y2-Y1)² )
So :
A ( -1 ; 5) B ( 0 ; 4)
Here X2 is 0 ; X1 is -1
Y2 is 4 and Y1 is 5
So :
( 0 - (-1) )² = 1² = 1
( 4 -5) ² = ( -1)² = 1
So Distance
=
So As
≈ 1.41 as nearest tenth, 1.4 is distance between A and B
I let you apply formula to point C and D , as it is the only way you will learn.
Do it step by step and all will flow nicely.