What happens when you add opposite? why do you want to get opposites coefficients for one of the variables?

George has seven boxes of five pencils. giulio three boxes of eight pencils. one of the boys arranges all his pencils equally into two groups. was this george or giulio how many are in each group explain

If x = -2, then x 2-7x+10 equals a. 0 b.20 c.28

Afamily has five members. a mom, a dad, two sisters, & a brother. the family lines up single file. what is the probabillity that the mom is at the front of the line