this is 5th grade question. Don't need to do 方程题. they will lear

 方程题 late (坐标图上给两点。告诉你是这两点在一条直线上。问这直线的斜率). this is not a real 方程题 for 5th kid. you made this simple question complicated and confused your kid. This is the american way of learning math.

  Two level of gf: academically talented or intellectually gifted