7.已知在平行四边形ABCD中,∠A=36°,则∠C为( )
| A. | 18° | B. | 36° | C. | 72° | D. | 144° |
4.如果不等式组$\left\{\begin{array}{l}{10-2x>0}\\{x-m≥0}\end{array}\right.$有解,那么m的取值范围是( )
| A. | m>5 | B. | m≥5 | C. | m<5 | D. | m≤5 |
3.一元二次方程(x+1)2=27的解为( )
0 285569 285577 285583 285587 285593 285595 285599 285605 285607 285613 285619 285623 285625 285629 285635 285637 285643 285647 285649 285653 285655 285659 285661 285663 285664 285665 285667 285668 285669 285671 285673 285677 285679 285683 285685 285689 285695 285697 285703 285707 285709 285713 285719 285725 285727 285733 285737 285739 285745 285749 285755 285763 366461
| A. | x1=2,x2=4 | B. | x1=2,x2=-4 | ||
| C. | x1=1+3$\sqrt{3}$,x2=1-3$\sqrt{3}$ | D. | x1=-1+3$\sqrt{3}$,x2=-1-3$\sqrt{3}$ |