a,tim x biet |x-2|+|3-2x|=2x+1
b,tim x,y thuoc Z biet xy+2x-y=5
c, tinh A=(1-1/15)(1-1/21)(1-1/28).....(1-1/210)
Tim (x,y) nguyen biet a) x + y = x : y = xy b) 2x + 3y + 3xy = 7
Tim (x,y) nguyen biet
a) x + y = x : y = xy
b) 2x + 3y + 3xy = 7
Tim x, y, z biet 2x=5y và xy =40
tim x,y,z biet : 5x=2y,2x=3z va xy=90
tim x,y biet
xy-4x+y=5
tim x biet
\(xy+2x+y=-1\)1
a, Tim x biet:/x-2/+/3-2x/=2x+1
b, Tim x,y thuoc Z biet:xy+2x-y=5
c, tim x,y,z, biet :2x=3y;4y=5zva 4x-3y+5z=7
Tim 2 so x va y biet
x/2=y/5 va xy=10