x×
=18×
×
x=9
26.(12分)用递等式计算.
121+1530÷15 3.25×2﹣2.6 ﹣
﹣
9.3÷2.5÷4 ×
+
÷
÷[
×(
+
)].
【分析】(1)先算除法,再算加法;
(2)先算乘法,再算减法;
(3)通分计算;
(4)运用除法的运算性质简算;
(5)运用乘法分配律简算;
(6)先算小括号内的,再算中括号内的,最后算括号外的.
【解答】解:(1)121+1530÷15
=121+102
=223
(2)3.25×2﹣2.6
=6.5﹣2.6
=1.9
(3)﹣
﹣
=﹣
﹣
=
(4)9.3÷2.5÷4
=9.3÷(2.5×4)
=9.3÷10
=0.93
(5)×
+
÷
=×
+
×
=(+
)×
=1×
=
(6)÷[
×(
+
)]
=÷[
×
]
=÷2
=
27.(6分)如图,在正方形网格中,ABC是直角三角形.
①画出三角形绕点A逆时针旋转90°后的图形.
②把旋转后的图形向左平移4格.
③画出原三角形ABC按2:1放大后的图形.