Math+Group+2

__perimeter-__ distance around something is the distance around anything []2 1

__rhombus__ has 2 parallel lines //. i choose this one because it is more described. tilted squarelike polygon paralelagram

__Algebraic expression__ a problem with no = at the end (n+15) - I picked this one because they showed a good example and showed what a algebraic expression was and what it looks like. a number and variable

__mixed number__ whole number plus fraction - it is the definition 2 1/3 two numbers

__compatible numbers__ numbers that are equal 1/3=33% 2.5=1 1/2- it is an example