Question

Add x² − a², −5x² + 2a², −4x² + 4a²

Answer 1

Required sum = x² − a² + (−5x² + 2a²) +( −4x² + 4a² )
Rearranging and collecting the like terms = x² -5x² -4x² -a² + 2a² +4a²
= (1-5-4)x² +(-1+2+4)a²
= -8x² + 5a²