ABCD-parallelogram. Find its perimeter if the perimeter is Pabd = 25 and bd = 10.

To find the perimeter of parallelogram ABCD, add the lengths of all sides.
If we subtract the length of the diagonal from the perimeter of the triangle ABD, which is half of the parallelogram which is formed by the two sides of the parallelogram and the diagonal, we will find out the sum of the lengths of the two sides.
A parallelogram has equal opposite sides.
1) 25 – 10 = 15 – the sum of the two sides;
2) P = 15 * 2 = 30.
Answer: P = 30.