Congruent triangles pls help

Drag the tiles to the boxes to form correct pairs. not all tiles will be used. match each set of vertices with the type of quadrilateral they form

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

What is the answer to this question? i'm a bit stumped. also how do i do it? 5(x - 4) = 2(x + 5)