Question

find the sum of the following

4a²,-5a²,-3a²,7a²

Answer 1

4a^2 , -5a^2 , -3a^2 , 7a^2 
sum = 4a^2 + (- 5a^2) + ( -3a^2) + 7a^2
= 4a^2 - 5a^2 - 3a^2 + 7a^2
= (4a^2 + 7a^2) - ( 5a^2 + 3a^2) 
= 11a^2 - 8a^2
= 3a^2

Answer 2

the sum of the following is :
4a²+7a²-5a²-3a²
=11a²-8a²
=3a²