Find the coordinates of the vertex B of the parallelogram ABCD, if A (0; 0), C (5; 7), D (3; 0).

First, let’s define what a parallelogram is. A parallelogram is a quadrangle whose opposite sides are equal and parallel.

According to the condition of the problem, we are given three points A, C, D, from their coordinate data we will find these points and designate them on the coordinate plane. Now, having connected these points together, we can define the fourth. By connecting points A, C, D, we see that the AD side of our parallelogram is 3 cm, which means CB will also be three centimeters. We build from point C a segment parallel to segment AD, measure 3 cm, find point B. Its coordinates are 8 on the abscissa axis, 7 on the ordinate axis (8; 7). Completing the parallelogram.