Current location - Training Enrollment Network - Mathematics courses - 4. There must be a process to correct mistakes in junior two mathematics. Please help me, I will definitely adopt it.
4. There must be a process to correct mistakes in junior two mathematics. Please help me, I will definitely adopt it.
80*0.3+90*0.2+85*0.5=84.5

X=3, y=-(-2)=2, so x+y=5, because it is symmetrical about X.

22/3 is an infinite cycle decimal, so it is not an irrational number. The cube root of -27 is -3, which is a rational number.