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①(d8+16-d4)×(-七4)②-七七+d×(-1)4-(-4)×5③da七+5-七a七-七a+da-8④d(-as+七a)-七(da-s)

题目详情
①(
d
8
+
1
6
-
d
4
)×(-七4)
②-七+d×(-1)4-(-4)×5
③da+5-七a-七a+da-8
④d(-as+七a)-七(da-s)
▼优质解答
答案和解析
①(
3
8
+
1
6
-
3
4
)×(-24),
=
3
8
×(-24)+
1
6
×(-24)-
3
4
×(-24),
=-9-4+18,
=5;

②-22+3×(-1)4-(-4)×5,
=-4+3+20,
=19;

③3a2+5-2a2-2a+3a-8,
=a2+a-3;

④3(-ab+2a)-2(3a-b),
=-3ab+6ab-6a+2b,
=3ab-6a+2b.