Help please! any1 know this

What is the missing statement in step 4? ? rts ? ? vtu and ? rtu ? ? vts ? rts ? ? rvs and ? rtu ? ? stv ? vrs ? ? vru and ? usr ? ? usv ? vur ? ? vus and ? uvs ? ? sru

Factor and solve to find roots x squared -x - 90 =0

Your best friend told you that last week scientists disco y that las vegas is responsible for abrupt climate changes. which do you think is best way to research that recent discovery? an encyclopedia usgs internet site a book in the library your best friend’s parents for your ! ❤️