3X(3)+5X(2)=9,7X(3)+9X(2)=7
4个回答
3X(3)+5X(2)=9①,
7X(3)+9X(2)=7②
①*7-②*3得8x^2=42
x=√21/2或-√21/2
相关问题
x-([1/3]+[2/3])=[7/12] 2x+[7/9]=[7/9] 15x-4.5×2=51 7x+3x+26=
(9x²-2x+7)-(x²+3x-2) =9x²-2x+7+x²-3x+2 =
1.(7X-3X+5.9)/3=2.9
解下列方程3=11-X;3-X=7;2X+3=X-1;2X-1=-X+5;11/9X+2/7=2/9X-5/7;1/2X
21-x/2+x/3-2x/5=x x+2/3+x=10-2x/7 9-3x-2/5=7-3x/6
(x^4+3x^3+5x^2+7x+9)/(x^2+2)
(x^4+3x^3+5x^2+7x+9)/(x^2+2)
7x=2+3x 3.5x=28 5(x+8)-5=6(2x-7) 9(x-4)=7(4-x)
7-9x/2-3x -4x-5/2-3x =1 x=?
若x2+3x+5=7,则3x2+9x-2= ___ .