Respuesta :
This one is a bit confusing but I'll try to answer. Since the sum is given and one of the addend is given, we need to perform subtraction to get the other addend.
8d⁵ - 3c³d² + 5c²d³ - 4cd⁴ + 9 ⇒ SUM
- 2d⁵ - c³d² + 8cd⁴ + 1 ⇒ 1ST ADDEND
6d⁵ - 2c³d² + 5c²d³ -12cd⁴ - 8 ⇒ 2ND ADDEND
8d⁵ - 3c³d² + 5c²d³ - 4cd⁴ + 9 ⇒ SUM
- 2d⁵ - c³d² + 8cd⁴ + 1 ⇒ 1ST ADDEND
6d⁵ - 2c³d² + 5c²d³ -12cd⁴ - 8 ⇒ 2ND ADDEND