Tim x
(x+3) x (5x-20) = 4-x
can gap
Tim x
(x+3) x (5x-20) = 4-x
\(\left(x+3\right)\left(5x-20\right)=4-x\)
\(\Leftrightarrow5x^2-5x-60=4-x\)
\(\Leftrightarrow5x^2-4x-64=0\)
\(\Leftrightarrow\orbr{\begin{cases}x=4\\x=-\frac{16}{5}\end{cases}}\)
P/s haphuong
tim x,y thuoc Z
a)5x.(-x)^2+1=6
4.x^3=4x
xy=x+y
xy=x-y
giai giup mik nha mik can gap
a) 5x.(-x)2 + 1 = 6
<=> 5x.x2 = 5
<=> 5x3 = 5
<=> x3 = 1
<=> x = 1
b) 4.x3 = 4x
4x3 - 4x = 0
4x.(x2 - 1) = 0
\(\Leftrightarrow\orbr{\begin{cases}4x=0\\x^2-1=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=0\\x^2=1\end{cases}}\)
Với \(x^2=1\)
\(\Leftrightarrow\orbr{\begin{cases}x=1\\x=-1\end{cases}}\)
c) xy = x + y
x + y - xy = 0
x + y - xy - 1 = 0
(x - xy) - (1 - y) = 0
x(1 - y) - (1 - y) = 0
(x - 1)(1 - y) = 0
\(\Leftrightarrow\orbr{\begin{cases}x-1=0\\1-y=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=1\\y=1\end{cases}}\)
d) Tương tự
1:Tim x biet a, 15-5x=0 b,2(x-1)+3(x+3)=-8 GIAI GIUP MINK NKE MINK DANG CAN GAP TRONG DEM NAY A
b.
\(2\left(x-1\right)+3\left(x+3\right)=-8\\ \Leftrightarrow2x-2+3x+9=-8\\ \Leftrightarrow5x+7=-8\\ \Leftrightarrow5x=-15\\ \Leftrightarrow x=-3\)
a, 15-5x=0
=> 5x= 15-0
=> 5x= 15
=> x= 15:5
=> x= 3
tim a,b de 5x^4+6x^3+ax-8x-20 chia het x^2+x-b
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 $x=2$
-19-x=-20 ; x-45=-17 ; -32-(x-5)=0 , x+5=0 toi nay m can ket qua gap 4 phep tim x nay cac ban giai gap giup m nhe
-19 - x = -20
=> x = - 19 + 20
= x = 1
vậy_
chị lớp 6 mà... vậy
-19 - x = -20
x = -19 + 20
x = 1
x - 45 = -17
x = -17 + 45
x = 28
-32 - ( x - 5 ) = 0
x - 5 = -32 - 0
x - 5 = -32
x = -32 + 5
x = -27
x + 5 = 0
x = 0 - 5
x = -5
a) tim gia tri nho nhat cua bieu thuc : A = | 1-x | + 8
b) tim cac so nguyen x biet 13 la boi cua x - 4
c) tim so nguyen x sao cho ( x + 5 ) chia het cho ( x + 3 )
giup minh voi! minh can gap gap gap.....
Cho bang tan so sau, hay tim gia tri x
Gia tri (x)|40| 50| 60| x| 90|100|
Tan so (n)|3|4| 4| 5| 3|1|N=20
Biet x = 66,5
Giup Minh vs Minh can gap
Theo đề bài ta có: Trung bình cộng: 66,5
=> 40.3+50.4+60.4+x.5+90.3+100.1 / 20 = 66,5
=> 930+5x = 66,5.20
=> 930+5x = 1330
=> 5x = 1330-930
=> 5x = 400
=> x = 400/5 = 80
Chúc bạn học tốt ^^
Tim x :
a ) 5x - 1 = 13
b ) ( x - 2 ) = 0
c ) 5 ( x - 7 ) + 8 = 0
d ) ( x - 19 ) * 4 = 36
e ) 3 ( x - 7 ) - 2 = 4
Giup minh voi ! Minh dang can gap lam !
a, 5x - 1 = 13
=> 5x = 14
=> x = 14/5
b,(x - 2) = 0
=> x - 2 = 0
=> x = 2
c, 5(x - 7) + 8 = 0
=>5(x - 7) = -8
=>x -7 = -8/5 = -1,6
=>x = 5,4
d, (x - 19).4 = 36
=>x - 19 = 9
=>x = 28
e, 3(x - 7) - 2 = 4
=> 3(x - 7) = 6
=> x - 7 = 2
=> x = 9