8.已知$\sqrt{2x+1}$+2y2$-2\sqrt{2}$y=-1,求$\frac{x}{y}$的值是( )
0 283487 283495 283501 283505 283511 283513 283517 283523 283525 283531 283537 283541 283543 283547 283553 283555 283561 283565 283567 283571 283573 283577 283579 283581 283582 283583 283585 283586 283587 283589 283591 283595 283597 283601 283603 283607 283613 283615 283621 283625 283627 283631 283637 283643 283645 283651 283655 283657 283663 283667 283673 283681 366461
| A. | -$\frac{\sqrt{2}}{2}$ | B. | $\frac{\sqrt{2}}{2}$ | C. | -$\sqrt{2}$ | D. | $\sqrt{2}$ |