Idon't know how to answer it proportional and if it is how do you it's not why is it not?

The border line of the linear inequality 4x + 7y < 5 is dotted true or false?

Find the area of an equilateral triangle with a side of 6 inches

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.