84:x =6× 7
84÷x=42
x=84:42
x=2
_________
84:2=6×7
42=42
<span>(a^3-6a^2+2a^4)-(*)=8a^2-3a^4+1,
</span>(*)=(a^3-6a^2+2a^4)-(8a^2-3a^4+1)=a^3-6a^2+2a^4-8a^2+3a^4-1=5a^4+a^3-14a^2-1
1. 59 + 64 = 123
2. 123 * 7 = 861
3. 160/2 = 80
4. 43*20 = 860
5. 961 - 861 = 100
6. 100 - 80 = 20
7. 20 + 860 = 880