Help i don't understand

The perimeter of △cde is 55 cm. a rhombus dmfn is inscribed in this triangle so that vertices m, f, and n lie on the sides cd , ce , and de respectively. find cd and de if cf=8 cm and ef=12 cm. the answer is not cd=20 and de=15. i have tried that one, it does not work.

What is the answer key for unit 7 polygon and quadrilaterals homework 6 trapezoids

Which graph represents the same relation as the table below? x f(x) –2 5 0 1 1 –1 2 –3