(3m+2n)(7m-6n)
网友回答
原式=3m(7m-6n)+2n(7m-6n)
=21m²-18mn+14mn-12n²
=21m²-4mn-12n²
======以下答案可供参考======
供参考答案1:
3X+Y=K+1 (1)
X+4Y=3 (2)
(1)*5-(2)*4
15X+5Y-4X-16Y=5K+5-12
11X-11Y=5K-7
2103所以33/11X+4Y=3 (2)
(1)*5-(2)*4
15X+5Y-4X-16Y=5K+5-12
11X-11Y=5K-7
2103所以33/11