Balls colliding on a pool table are an example of how energy changes when objects collide. when two balls collide, the first ball loses speed and the second ball moves. what is the combined distance the two balls traveled? 5/10m + 33/100m

because linear equations are a lot simpler than quadratics equations, and linear equations formula is a lot easier to memorize. that's why i think they're harder.

6mm^3 or .6cm^3

      216

      /   \

  36     6

  /   \     /

6     6   6

factor trees are nice.