(2.5p−1.5q)2−(1.5p−2.5q)2
Using identity (a−b)2=a2−2ab+b2 =6.25p2−7.5pq+2.25q2−(2.25p2−7.5pr+6.25q2)=6.25p2−7.5pq+2.25q2−2.25p2+7.5pq−6.25q2)=4p2−4q2
Question 4(v) Simplify: (2.5p−1.5q)2−(1.5p−2.5q)2