Step-by-step explanation:
1. draw the parallelogram with side 20cm and 25cm respectively and also the diagonal as well.
2.Clearly it forms a triangle in the parallelogram with three known lengths of side.
3.Using the cosine rule : c^2=b^2+c^2 -2bc cos c to find the obtuse angle.
First, you try to make sure that both the denominators are the same. In order to do this, you multiply both fractions' numerator and denominator by the other fraction's denominator. Next, you combine like terms in the numerator, and then you simplify the fraction.
Since the center is considered the corner that they both share, here are the answers figure a goes with the first, figure b goes with the last, figure c goes with the second, and figure d goes with the third. Hope this helps.