10.将代数式x2-(2x+y-z)去掉括号后应为( )
| A. | x2-2x+y-z | B. | x2-2x-y+z | C. | x2+2x+y-z | D. | x2+2x-y+z |
9.下图中几何体的截面是长方形的是( )
0 286126 286134 286140 286144 286150 286152 286156 286162 286164 286170 286176 286180 286182 286186 286192 286194 286200 286204 286206 286210 286212 286216 286218 286220 286221 286222 286224 286225 286226 286228 286230 286234 286236 286240 286242 286246 286252 286254 286260 286264 286266 286270 286276 286282 286284 286290 286294 286296 286302 286306 286312 286320 366461
| A. | B. | C. | D. |