tim x thuoc z biet x+5:x-2
tim x thuoc Z biet |x-2| - 5(x-4) = 20 - 5x
Lời giải:
Nếu $x\geq 2$ thì:
$x-2-5(x-4)=20-5x$
$x-2=20-5x+5(x-4)=0$
$\Rightarrow x=2$ (tm)
Nếu $x<2$ thì:
$2-x-5(x-4)=20-5x$
$2-x=20-5x+5(x-4)=0$
$\Rightarrow x=2$ (loại do $x<2$)
Vậy $x=2$
tim x thuoc z,biet
(x-5)^2=0
\(\left(x-5\right)^2=0\)
\(\Rightarrow x-5=0\)
\(\Rightarrow x=0+5\)
\(\Rightarrow x=5\)
Vậy x=5
(x - 5)2 = 0
=> (x - 5)2 = 02
=> x - 5 = 0
=> x = 0 + 5
=> x = 5
Vậy x = 5
(x - 5)2 = 0
=> (x - 5)2 = 02
=> x - 5 = 0
=> x = 0 + 5
=> x = 5
tim x, y thuoc Z biet : x.y - 2.x - 3.y = 5
xy - 2x - 3y = 5
<=> xy - 2x - 3y + 6 = 11
<=> x(y - 2) - 3(y - 2) = 11
<=> (x - 3)(y - 2) = 11
x - 3 | 1 | -1 | 11 | -11 |
y - 2 | 11 | -11 | 1 | -1 |
x | 4 | 2 | 14 | -8 |
y | 13 | -9 | 3 | 1 |
Vậy...
tim x thuoc z biet (x-5)^x+1-(x-5)^x+5
cho a thuoc z biet :
a cong x bang 5
a - x bang 2
tim a,b thuoc z biet :
a công x bằng b
a trừ x bằng b
tim cac so x,y,z thuoc Q biet rang (x+y):(5-z):(y+z):(y+9)=3:1:2:5
Ta có:(x+y):(5-z):(y+z):(y+9)=3:1:2:5
=> 5-z=1=>z=4.
y+9=5=>y=-4.
x+y=3=>x-4=3(do y=-4)=>x=7.
Vậy x=7,y=-4,z=4.
tim x, y thuoc Z biet : x.y - 2.x - 3.y = 5 ( trinh bay nha )
tim x thuoc Z biet x-5 chia het cho 7-x
tim x, y thuoc Z biet 3/x/ phan 2 +5/y/ phan 3=8