What is the common ratio of the geometric sequence shown below
-2,4,-8,16

What is r i 4.5+10r=-6.5 with work pls

I’m confused on how to work the pie charts

The figure shows triangle def and line segment bc, which is parallel to ef: triangle def has a point b on side de and point c on side df. the line bc is parallel to the line ef. part a: is triangle def similar to triangle dbc? explain using what you know about triangle similarity. part b: which line segment on triangle dbc corresponds to line segment ef? explain your answer. part c: which angle on triangle dbc corresponds to angle f? explain your answer. asap