5y-9＝7y-13

5y-9＝7y-13 [T,Y]=ode45(@rigid,[0 1],[rand(15,1)]);plot(T,Y(:,1),'-',T,Y(:,2),'-.',T,Y(:,3),'.',T,Y(:,4),'-',T,Y(:,5),'-.',T,Y(:,6),'.',T,Y(:,7),'-',T,Y(:,8),'-.',T,Y(:,9),'.',T,Y(:,10),'-',T,Y(:,11),'-.',T,Y(:,12),'-.',T,Y(:,13),'.',T,Y(:,14),'-',T,Y(:,15),'.') 4x+9y=12 3y-2y+5z=11 5x-6y+7z=13 求：x y z等于多少 解不等式组2y+3小于9-y,6y-1＜5,3y+7≥2-y 已知X＝11Y,（X－2）*3＝Y,（X－4）*5＝Y,（X－6）*7＝Y,（X－8）*9＝Y ,求X、Y各是多少? 已知整数x,y,使得7能整除13x+8y,求证：7能整除9x+5y 已知整数x,y,使得7|（13x+8y）,求证：7|(9x+5y) 解这些方程组 (1) 7x-2y=96 5x-3y=45 (2) 4x+2y=50 2x+3y=47 (3) 4x+2y=66 7x-3y=70(4) 11x+9y=49 13x-3y=17 (5) 2y-x=1 13x-8y=59 (6) 18x+29y=307 16x+28y=284 三元一次方程解 1.{x+y-z=5 {3x+2y+z=2 {2x-2y+z=-31.{x+y-z=5 2.{9x-5y+x=-6 3.{x-y=3 4.{x+y=3 5.{4x-2y+z=7{3x+2y+z=2 {9x+y-2z=3 {x+z=7 {y+z=4 {2x-y-3z=28{2x-2y+z=-3 {-9x+3y-5z=0 {y-z=6 {z+x=5 {x+y-2z=13 9－3y＝5y＋5 2(y-4)(3y+2)-5(-3y+7)(y+1),其中y=-1 {y=x+3,7x+5y+9; Y=x+3 7x+5y=9 y-x=3 7x+5y=-9 y=x+3 7x+5y=9 (3y-1)/4-1=(5y-7)/6 9y-3-3=10y-14 9y-10y=-14+3+3 -y=-8 y=8 ..1.x+y+z=26,2.4y+3z=7,y-z=1,3x+2z=17,x+2y-z=18 9x-7y=173.x-7y+3z=17 4.2x+4y+3z=95x-6y-z=24 3x-2y+5z=113x+7y-2z=1 5x-6y+7z=131.x+y+z=26,y-z=1x+2y-z=18 2.4y+3z=7,3x+2z=11,9x-7y=17 3.x-7y+3z=17 5x-6y-z=24 3x+7y-2z=14.2x+4y+3z=93x-2y+5z=11 5x-6y+7z=13 代数式2y²+3y+7＝18,求4y²+6y-9的值