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)5/x=2/10
<=>2x=5.10
<=>2x=50
<=>x=25
=>5/25=y/-15
=>y/-15=1/5
=>y=-15/5=-3
b)x/-6=3/9
<=>x/-6=1/3
<=>x/-6=2/6=-2/-6
<=>x=-2
4/y=3/9
<=>4/y=1/3
<=>4/y=4/12
<=>y=12
a,\(\frac{5}{x}=\frac{y}{-15}=\frac{2}{10}\)
\(\frac{2}{10}=\frac{1}{5}\)
Nên Ta có:
\(\frac{5}{x}=\frac{y}{-15}=\frac{1}{5}\)
<=> x = 5.5
<=> x = 25
Vậy, x = 25
<=> 5y = -15
<=> y = -15:5
<=> y = -3
Vậy, y = -3
b, \(\frac{x}{6}=\frac{4}{y}=\frac{3}{9}\)
Mà \(\frac{3}{9}=\frac{1}{3}\)
Nên Ta có:
\(\frac{x}{6}=\frac{4}{y}=\frac{1}{3}\)
<=> 3x=6
<=> x = 6:3
<=> x = 2
Vậy, x = 2
<=> y = 4.3
<=> y =12
Vậy, y = 12