First and foremost that is a quadrilateral, because it is a 4-sided figure. If it was a trapezoid it would have only 1 set of parallel lines. So NOT a trapezoid. It is a parallelogram because parallelograms have 2 pair of parallel lines. It is not a rhombus because a rhombus has 4 equal length sides. So it's not a square either. It is not a rectangle either because rectangles have 4 right angles and this one does not. So your choices are 1 and 3.
Answer:
Here's what I got. First of all, did you meant y=mx+b+mx+mxy+mx=b, because that's undefined, or did you meant y=mx+b+mx+mx, which is b=−3mx+y.