tim x dua vao quan he uoc boi:tim so tu nhien x sao cho x-1 la uoc cua 12tim so tu nhien x sao cho 2x+1 la uoc cua 28tim so tu nhien x sao cho x+15 la boi cua x+3tim cac so nguyen x,y sao cho (x+1)(y-2)=3tim so nguyen x sao cho(x+2).(y-1)=2tim so nguyen to x vua la uoc cua 275 vua la uoc cua 180tim so nguyen to x,y biet x+y=12 va UCLL (x:y)=5tim so tu nhien x,y biet x+y=32 va UCLL (x:y)=8tim so tu nhien x biet x chia het cho10; xchia het cho12; x chia het cho15 va 100<x<150tim so x nho nhat khac 0b...
Đọc tiếp
tim x dua vao quan he uoc boi:
tim so tu nhien x sao cho x-1 la uoc cua 12
tim so tu nhien x sao cho 2x+1 la uoc cua 28
tim so tu nhien x sao cho x+15 la boi cua x+3
tim cac so nguyen x,y sao cho (x+1)(y-2)=3
tim so nguyen x sao cho(x+2).(y-1)=2
tim so nguyen to x vua la uoc cua 275 vua la uoc cua 180
tim so nguyen to x,y biet x+y=12 va UCLL (x:y)=5
tim so tu nhien x,y biet x+y=32 va UCLL (x:y)=8
tim so tu nhien x biet x chia het cho10; xchia het cho12; x chia het cho15 va 100<x<150
tim so x nho nhat khac 0b biet x chia het cho 24 va 30
40 chia het cho x . 56 chia het cho x va x>6
a) Ta có: \(\left(x-\frac{1}{3}\right)^2-\frac{1}{4}=0\)
\(\Rightarrow\left(x-\frac{1}{2}\right)^2=\frac{1}{4}\)
\(\Rightarrow x-\frac{1}{2}=\frac{1}{2}\Rightarrow x=1\)
hoặc \(x-\frac{1}{2}=-\frac{1}{2}\Rightarrow x=-\frac{1}{2}+\frac{1}{2}=0\)
Vậy \(x\in\left\{1;0\right\}\)
b)\(20\%.x+\frac{2}{5}x=x-4\)
\(\Rightarrow\frac{1}{5}x+\frac{2}{5}x-x=-4\)
\(\Rightarrow\frac{-2}{5}x=-4\)
\(\Rightarrow x=-4:\left(-\frac{2}{5}\right)=10\)
Vậy x=10
c) 3(x+1)+4(x+3)-2(x+16) = 18
=> 3x+3+4x+12-2x-32 =18
=> (3x+4x-2x)+(3+12-32)=18
=> 5x - 17 = 18
=> 5x = 18 + 17 = 35
=> x = 35 : 5 = 7
Vậy x = 7
sao3x+3 rồi 4x +12 là sao mình hk hiểu