Factor: a² + 9a+20
A
(a-4)(-5)
B (a+2)(a +10)
C (-2)(a-10)
D (a+4)(a +5)

At the olympic games, many events have several rounds of competition. one of these events is the men's 100-meter backstroke. the upper dot plot shows the times (in seconds) of the top 8 finishers in the final round of the 2012 olympics. the lower dot plot shows the times of the same 8 swimmers, but in the semifinal round. which pieces of information can be gathered from these dot plots? (remember that lower swim times are faster.) choose all answers that apply: a: the swimmers had faster times on average in the final round. b: the times in the final round vary noticeably more than the times in the semifinal round. c: none of the above.

The hockey team has been great! in 2008, they won 20% more games than in 2007 in 2009 they won 50% more games than in 2008 what was their overall percentage increase from 2007 through2008?

Find the value of x. also give me an explanation so i can complete it to other questions as well, : )