Question

-[3a^2-2a^2+9a^2-{6a^2-(-2a^2+3a^2)}]​

Answer 1

Answer:

-[3a^2-2a^2+9a^2+{6a^2-(-2a^2+3a^2)}]

= -[3a^2-2a^2+9a^2+{6a^2+2a^2-3a^2}]

= -[3a^2-2a^2+9a^2+6a^2+2a^2-3a^2]

= -3a^2+2a^2-9a^2-6a^2-2a^2+3a^2

• now -3a^2 and +3a^2 will get cancelled
• and +2a^2 and -2a^2 will get cancelled
• remaining: -9a^2 and -6a^2

-9a^2 -6a^2

= -15a^2