8.
如图,正方形纸片ABCD的边长为4cm,点M、N分别在边AB、CD上.将该纸片沿MN折叠,使点D落在边BC上,落点为E,MN与DE相交于点Q.随着点M的移动,点Q移动路线长度的最大值是( )
| A. | 4cm | B. | 2cm | C. | $\sqrt{2}$cm | D. | 1cm |
3.若等腰三角形两边长满足方程x2-7x+6=0,则这个三角形的周长为( )
| A. | 8 | B. | 13 | C. | 8或13 | D. | 不确定 |
2.一个直角三角形的三边分别为3,4,a,那么a的取值是( )
0 286032 286040 286046 286050 286056 286058 286062 286068 286070 286076 286082 286086 286088 286092 286098 286100 286106 286110 286112 286116 286118 286122 286124 286126 286127 286128 286130 286131 286132 286134 286136 286140 286142 286146 286148 286152 286158 286160 286166 286170 286172 286176 286182 286188 286190 286196 286200 286202 286208 286212 286218 286226 366461
| A. | $\sqrt{7}$ | B. | 5 | C. | $\sqrt{7}$或5 | D. | 无法确定 |