12.5/6.72 get this right

Can somebody 1. what is the formula for finding the vertical distance between two points on a coordinate plane?

Given: ae ≅ ce ; de ≅ be prove: abcd is a parallelogram. we have that ab || dc. by a similar argument used to prove that △aeb ≅ △ced, we can show that △ ≅ △ceb by. so, ∠cad ≅ ∠ by cpctc. therefore, ad || bc by the converse of the theorem. since both pair of opposite sides are parallel, quadrilateral abcd is a parallelogram.

Renting a room at the willow tree resort costs $125 for 2 people. each additional person is $25. write an expression that shows the cost for n extra people