若X1,X2,X3,X4,X5 满足方程组:2X1+X2+X3+X4+X5=6,①X1+2X2+X3+X4+X5=12 ②X1+X2+2X3+X4+X5=24 ③X1+X2+X3+2X4+X5=48 ④X1+X2+X3+X4+2X5=96 ⑤⑴求X1+X2+X3+X4+X5的值;⑵求3X3+2X4-X5有必要说明一下,凡是跟在X后面的数字都是小
来源:学生作业帮助网 编辑:作业帮 时间:2024/05/04 22:32:02
若X1,X2,X3,X4,X5 满足方程组:2X1+X2+X3+X4+X5=6,①X1+2X2+X3+X4+X5=12 ②X1+X2+2X3+X4+X5=24 ③X1+X2+X3+2X4+X5=48 ④X1+X2+X3+X4+2X5=96 ⑤⑴求X1+X2+X3+X4+X5的值;⑵求3X3+2X4-X5有必要说明一下,凡是跟在X后面的数字都是小
若X1,X2,X3,X4,X5 满足方程组:
2X1+X2+X3+X4+X5=6,①
X1+2X2+X3+X4+X5=12 ②
X1+X2+2X3+X4+X5=24 ③
X1+X2+X3+2X4+X5=48 ④
X1+X2+X3+X4+2X5=96 ⑤
⑴求X1+X2+X3+X4+X5的值;
⑵求3X3+2X4-X5
有必要说明一下,凡是跟在X后面的数字都是小数子,比如说X1=X小1
若X1,X2,X3,X4,X5 满足方程组:2X1+X2+X3+X4+X5=6,①X1+2X2+X3+X4+X5=12 ②X1+X2+2X3+X4+X5=24 ③X1+X2+X3+2X4+X5=48 ④X1+X2+X3+X4+2X5=96 ⑤⑴求X1+X2+X3+X4+X5的值;⑵求3X3+2X4-X5有必要说明一下,凡是跟在X后面的数字都是小
①+②+③+④+⑤(等号左边、右边各相加)得到:
6*(x1+x2+x3+x4+x5)=6+12+24+48+96
x1+x2+x3+x4+x5=(6+12+24+48+96)/6
x1+x2+x3+x4+x5=31⑥
①-⑥得:x1=6-31=-25
②-⑥得:x2=12-31=-19
③-⑥得:x3=24-31=-7
④-⑥得:x4=48-31=17
⑤-⑥得:x5=96-31=65
3x3+2x4-x5=3*(-7)+2*17-65=-52
若X1,X2,X3,X4,X5 满足方程组:
2X1+X2+X3+X4+X5=6, ①
X1+2X2+X3+X4+X5=12 ②
X1+X2+2X3+X4+X5=24 ③
X1+X2+X3+2X4+X5=48 ④
X1+X2+X3+X4+2X5=96 ⑤
⑴求X1+X2+X3+X4+X5的值...
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若X1,X2,X3,X4,X5 满足方程组:
2X1+X2+X3+X4+X5=6, ①
X1+2X2+X3+X4+X5=12 ②
X1+X2+2X3+X4+X5=24 ③
X1+X2+X3+2X4+X5=48 ④
X1+X2+X3+X4+2X5=96 ⑤
⑴求X1+X2+X3+X4+X5的值;
⑵求3X3+2X4-X5
解1:1+2+3+4+5
6-X1=12-X2=24-X3=48-X4=96-X5=(X1+X2+X3+X4+X5)
6-X1+12-X2+24-X3+48-X4+96-X5=5(X1+X2+X3+X4+X5)
186-(X1+X2+X3+X4+X5)=5(X1+X2+X3+X4+X5)
(X1+X2+X3+X4+X5)=31
解2:3X3+2X4-X5
(X1+X2+X3+X4+X5)=31
X1+X2+X3+X4+2X5=96
X5=65
X1+X2+X3+2X4+X5=48
X4=17
X1+X2+2X3+X4+X5=24
X3=-7
3X3+2X4-X5
=3*(-7)+2*17-65
=-52
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