tim y biet (y+1)+(y+2)+(y+3)+ . . . +(y+9)+(y+10) =2012
bai 1: Tim x biet
\(\hept{\begin{cases}x-y=\frac{3}{10}\\y\left(x-y\right)=-\frac{3}{50}\end{cases}}\)
bai 2: Tim x, y biet:
x+\(\left(-\frac{31}{12}\right)^2\)=\(\left(\frac{49}{12}\right)^2\)-x=y2
Bai 9: Tim x,y,z biet:
(x-1)2+(x+y)2+(xy-z)2=0
a) thay \(x-y=\frac{3}{10}\)vào \(y\left(x-y\right)=\frac{-3}{50}\)ta có\(\frac{3}{10}y=\frac{-3}{50}\)=>\(y=\frac{-3}{50}:\frac{3}{10}=\frac{-1}{5}\)=>\(x-y=\frac{3}{10}\Rightarrow x=\frac{3}{10}+\frac{-1}{5}=\frac{1}{10}\)
hôm sau mik giải tip cho
Tim x,y biet: 25y-y^2= 8(x-2012)^2
tim x va y biet
a)x/18=y/15 va x-y=-30
b)7*x=9*y va 10*x-8*y=68
c)(x1/2)^50 +(y+1/3)^40=o
a)
\(\frac{x}{18}=\frac{y}{15},x-y=-30\)
\(\frac{x}{18}=\frac{y}{15}\)
\(\frac{x}{18}-\frac{y}{15}=0\)
\(-\frac{6y-5x}{90}=0\)
\(6y-5x=0\)
\(x-y=-30\)
\(-\left(y-x-30\right)=0\)
\(y-x-30=0\)
\(\Rightarrow x=-180;y=-150\)
dẫn tui bài y:9-8=15 với
tìm y biết :(y + 1 ) + ( y + 2 ) + ( y + 3 ) +.......+ ( y + 9 ) + ( y + 10 ) = 2012
( y + 1 ) + ( y + 2 ) + ( y + 3 ) + ......+ ( y + 9 ) + ( y + 10 ) = 2012
Suy ra có 10 số y
Tổng các số từ 1 đến 10 là : ( 10 + 1 ) x 10 : 2 = 55
y x 10 + 55 = 2012
y x 10 = 2012 - 55
y x 10 = 1957
y = 1957 : 10
y = 195,7
(y+y+y+...+y)+(1+2+3+...+10)=2012
yx10+55=2012
yx10=1957
y=1957:10
y=195,7
tim so nguyen x,y biet 42-3|y-3|=4(2012-x)^4
tim x,y,z biet x-y=2011,y-z=-2012,z+x=2013
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.
a, Tim x, y biet: x + y/2012 = xy/2013 = x - y/2014
Theo bài ra có:
(X+y+x-y):(2012+2014)=xy/2013
<=> 2x/4026 = xy/2013
=> y=1
(X+1):2012=x/2013
<=> 2013x+2013=2012x
X=-2013
a, Tim so tu nhien x, y biet rang 4<9/x<12/y<18
b, Tim so nguyen x, y biet rang x/2 - 2/y = 1/2
Lam cach nao de ra duoc ket qua nhu vay ha ban?