Evaluate (a+b)^3-12 when a=2 and b=1

One of the same side angles of two parallel lines is 20° smaller than the other one. find the measures of these two angles.

The following frequency table relates the weekly sales of bicycles at a given store over a 42-week period.value01234567frequency367108521(a) in how many weeks were at least 2 bikes sold? (b) in how many weeks were at least 5 bikes sold? (c) in how many weeks were an even number of bikes sold?

Given: and prove: what is the missing reason in the proof? given transitive property alternate interior angles theorem converse alternate interior angles theorem