Can someone explain to me why this is supposed to be 21 and not -21

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

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

Graph g(x)=2cosx . use 3.14 for π . use the sine tool to graph the function. graph the function by plotting two points. the first point must be on the midline and closest to the origin. the second point must be a maximum or minimum value on the graph closest to the first point.