The lines described by y=(3a-9)x and y= 1/7x are perpendicular. What is the value of a?

In the figure below, ∠dec ≅ ∠dce, ∠b ≅ ∠f, and segment df is congruent to segment bd. point c is the point of intersection between segment ag and segment bd, while point e is the point of intersection between segment ag and segment df. the figure shows a polygon comprised of three triangles, abc, dec, and gfe. prove δabc ≅ δgfe.

Given that abcd is a rhombus, what is the value of x?

4+(2+x) can you me solve this problem