Question

(question is given above in the picture)

Answer 1

let the coordinates be x and y
applythe distance formula and try

Answer 2

Hope u like my process
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Let the co-ordinates of B = (0, y)
Since, point B is on the y - axis

Given,
A= (4, 0)

AB = 5 units

AB ²= [ (x2 - x1)² +(y2 - y1)²]
$or. \: {5}^{2} = {(0 - 4) ^{2} - {(y - 0)}^{2} } \\ or. \: 25 = 16 + {y}^{2} \\ or. \: {y}^{2} - 9 = 0 \\ or. \: (y - 3)(y + 3) = 0 \\ so.. \\ \\ either \\ y = 3 \\ or \\ y = - 3$
Thus the co-ordinates of B are,
Either ,
( 0, 3)

or,
(0,-3)
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Hope this is ur required answer
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