如题所述
第1个回答 2020-04-04
解:21×3+3×53-3×4等于( 210 )
∵已知需求出21×3+3×53-3×4等于多少
X × Y - X × Z = X × (Y - Z)
∴21 × 3 + 3 × 53 - 3 × 4
= 3 × ( 21 + 53 - 4)
= 3 × (74 - 4)
= 3 × 70
= 210
答:21×3+3×53-3×4等于210
∵已知需求出21×3+3×53-3×4等于多少
X × Y - X × Z = X × (Y - Z)
∴21 × 3 + 3 × 53 - 3 × 4
= 3 × ( 21 + 53 - 4)
= 3 × (74 - 4)
= 3 × 70
= 210
答:21×3+3×53-3×4等于210
第2个回答 2020-04-04
用乘法分配律提取公因数3;
21x3+3x53-3x4
=3x(21+53-4)
=3x70
=210
21x3+3x53-3x4
=3x(21+53-4)
=3x70
=210
第3个回答 2020-04-04
提出公因式3∴这个式子变成了=3×(21+53-4)
=3×70
=3×70
第4个回答 2020-04-04
21x3+3X53一3x4
=3x(21+53一4)
=3X50
=150
=3x(21+53一4)
=3X50
=150
第5个回答 2020-04-04
=3*(21+53-4)=3*70=280