point A is on the y axis at a distance of 4 units from the origin.If coordinates of point B are (-3, 0), find the length of AB.

Plzzzzzz help fast!!!I have my board exams.

Since point A on y-axis, so its abscissa is always 0.

Now, its distance from the origin is 4 units.

Hence the coordinates of point A are (0, 4).

Point A is (0,4) and point B is (-3,0).

AB=$\sqrt{(x_2-x_1{)}^2+(y_2-y_1{)}^2}=\sqrt{(-3-0{)}^2+(0-4{)}^2}=\sqrt{25}=5$ units