Add the following
4a2+5b2-8c2,7a2+3b2,-b2+c2
To add two or more algebraic expressions, group the like terms of the expression and add each group of like terms separately.
The Sum
=(4a2+5b2-8c2)+(7a2+3b2)+(-b2+c2)=(4a2+7a2)+(5b2+3b2-b2)+(-8c2+c2) (grouping the like terms)
adding the numerical coefficient of like terms
=(4+7)a2+(5+3-1)b2+(-8+1)c2=11a2+(8-1)b2+(-7)c2=11a2+7b2-7c2