Could someone answer for this for me?

Kapil needed to buy a long wooden beam. he went to two sawmills that each charge an initial fee plus an additional fee for each meter of wood. the following equation gives the price (in dollars) of a wooden beam from the first sawmill as a function of its length (in meters). p = 5+20xp=5+20x

Consider the proof. given: segment ab is parallel to line de. prove: what is the missing statement in step 5?

Multiply. write your answer in simplest form. 3/8 x 5/7