A vector with an end at point (5; 3) has coordinates (3; 1). Find the ordinate of the point.

Obviously, a vector has a beginning and an end, because a vector is a directional segment.

Let’s call a vector AB, in which point A is the point of the beginning of the vector, point B is the point of the end of the vector with coordinates (5; 3). To find the coordinates of a vector, subtract the coordinates of the start from the coordinates of the end.

AB = {xB-xA; YB-YA}

Means Y = Yb-Ya, therefore Ya = Yb-Y;

Let’s make a calculation and get that Yа = 1-3 = -2;

Hence the ordinate of the origin point A (Xa; -2)

Answer: -2