(26+x)+124-(124-x)với x=2
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
125x - 26x + x = 124
x ( 125 - 26 + 1 ) = 124
100x = 124
x = 1,24
^^
a )
\(\Rightarrow\frac{x-100}{24}-1+\frac{x-98}{26}-1+\frac{x-96}{26}-1=0\)
\(\frac{x-124}{24}+\frac{x-124}{26}+\frac{x-124}{28}=0\)
\(\left(x-124\right)\left(\frac{1}{26}+\frac{1}{24}+\frac{1}{28}\right)=0\)
\(\Rightarrow x-124=0\Rightarrow x=124\)
a: 3x=2y
nên x/2=y/3
Áp dụng tính chất của dãy tỉ số bằng nhau, ta được:
\(\dfrac{x}{2}=\dfrac{y}{3}=\dfrac{x-y}{2-3}=\dfrac{1}{-1}=-1\)
Do đó: x=-2; y=-3
\(A=\left(-2\right)^3+12\cdot\left(-2\right)^2\cdot\left(-3\right)+48\cdot\left(-2\right)\cdot\left(-3\right)^2-64\cdot\left(-3\right)^3\)
\(=-8+12\cdot4\cdot\left(-3\right)-96\cdot9-64\cdot\left(-27\right)\)
\(=712\)
b: 6a=5b
nên a/5=b/6
Đặt a/5=b/6=k
=>a=5k; b=6k
\(B=\dfrac{2a-3b}{3b-2a}=-1\)
d: \(\left|x-2\right|+\left(y-1\right)^2=0\)
=>x-2=0 và y-1=0
=>x=2 và y=1
\(D=\left|2-2\right|+\dfrac{2-1}{2-1}=0+1=1\)
a,A=5x2z-10xyz+5y2z
=5z(x2-2xy+y2)
=5z(x-y)2
Thay x=124,y=24,z=2 vào A ta được:
A=5.2(124-24)2=10.1002=10000
b,B=2x2+2y2-x2z+z-y2z-2
=2(x2+y2)-z(x2+y2)+(z-2)
=(2-z)(x2+y2)-(2-z)
=(2-z)(x2+y2-1)
Thay x=1,y=1,z=-1 vào B
B=(2+1)(12+12-1)=3
c, C=x2-y2+2y-1
=x2-(y2-2y+1)
=x2-(y-1)2
=(x-y+1)(x+y-1)
=(75-26+1)(75+26-1)
=50.100=5000
\(\frac{x-28-124}{2011}+\frac{x-124-2011}{28}+\frac{x-2011-28}{124}=3\)
<=> \(\left(\frac{x-152}{2011}-1\right)+\left(\frac{x-2135}{28}-1\right)+\left(\frac{x-2039}{124}-1\right)=0\)
<=> \(\frac{x-2163}{2011}+\frac{x-2163}{28}+\frac{x-2163}{124}=0\)
<=> \(\left(x-2163\right)\left(\frac{1}{2011}+\frac{1}{28}+\frac{1}{124}\right)=0\)
<=> \(x-2163=0\)(vì \(\frac{1}{2011}+\frac{1}{28}+\frac{1}{124}\ne0\)
<=> \(x=2163\)
\(\frac{x-28-124}{2011}+\frac{x-124-2011}{28}+\frac{x-2011-28}{124}=3\)
<=> \(\frac{x-28-124}{2011}+\frac{x-124-2011}{28}+\frac{x-2011-28}{124}-3=0\)
<=> \(\left(\frac{x-28-124}{2011}-1\right)+\left(\frac{x-124-2011}{28}-1\right)+\left(\frac{x-2011-28}{124}-1\right)=0\)
<=> \(\frac{x-28-124-2011}{2011}+\frac{x-124-2011-28}{28}+\frac{x-2011-28-124}{124}=0\)
<=> \(\frac{x-2163}{2011}+\frac{x-2163}{28}+\frac{x-2163}{124}=0\)
<=> \(\left(x-2163\right)\left(\frac{1}{2011}+\frac{1}{28}+\frac{1}{124}\right)=0\)
Vì \(\frac{1}{2011}+\frac{1}{28}+\frac{1}{124}\ne0\)
=> \(x-2163=0\)
=> \(x=2163\)
(26 + x) + 124 - (124 - x)
= 26 + x + 124 - 124 + x
= 2x + 26
Với x = 2 ta có:
2.2 + 26 = 30
A = (26 + \(x\)) + 124 - (124 - \(x\))
Thay \(x\) = 2 vào A ta có:
A = (26 + 2) + 124 - (124 - 2)
A = 28 + 124 - 124 + 2
A = (28 + 2) + (124 - 124)
A = 30 + 0
A = 30