Given a=5x^2 and b=-3x^2+6 give the expression that represents a+b

Keisha makes a large sandwich for a family picnic she takes 1/2 of them the sandwich to the picnic her family eats 3/8 of the whole sandwich what fraction of the whole sandwich does keisha bring back from the picnic

Aye asap pls ! markin da brainiest too ! btw da step choices are all add, distribute, divide, n subtract

Jim had 15 minutes to do 5 laps around his school what would his time be