Help me ah please

I’m stuck on this i don’t understand.

Δabc is dilated by a scale factor of 3 with the origin as the center of dilation to form δa′b′c′. the slope of is -1.2. the length of is p units, the length of is q units, and the length of is r units. the slope of is . the length of is units.

For the following geometric sequence, find the recursive formula. {-80, 20, -5, } i need : ')