Please help with these four Geometry questions! It'd be very much appreciated.

In triangle abc segment de is parallel to the side ac . (the endpoints of segment de lie on the sides ab and bc respectively). find de, if ac=20cm, ab=17cm, and bd=11.9cm;

What is the value of x in the following equation? -3x-2=2x+8

The dash figure is a dilation if the original figure. find the scale factor. classify the dilation as an enlargement or a reduction