Find the value of x in parallelogram PQRS.

PT = y
TR = x + 3
QT = 2y
TS = 3x - 1

Solve the formula ax+ by = c for x.

Which equation is represented by the graph below?

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.