满足方程组2x+3y=k+2,3x+2y=k的x、y值得和为4,求k的值
问题描述:
满足方程组2x+3y=k+2,3x+2y=k的x、y值得和为4,求k的值
答
方程组2x+3y=k+2,3x+2y=k
加起来 5x + 5y = 2k +2
x + y = 2(k+1) / 5 = 4
的x、y值得和为4
解得 k+1 = 10
k = 9