\(\left(x+1\right)+\left(x+2\right)+...+\left(x+28\right)=153\)
\(\Leftrightarrow x+1+x+2+...+x+28=153\)
\(\Leftrightarrow28x+406=153\Leftrightarrow28x=153-406=-253\)
\(\Leftrightarrow x=\dfrac{-253}{28}\)
( x . 1 ) + ( x . 2 ) +......+ ( x + 28 ) = 155
tìm x
7 + 2^x-1=28-[4^2 - (2^2-1)]tìm x
A, (X+1)+(x+4)+(x+7)+...+(x+25)+(x+28)=155
b,(x+9)+(x-2)+(x+7)+(x-4)+(x+5)+(x-6)+(x+3)+(x-8)+(x+1)=95
Tìm số nguyên x:
2.(x-1)-5.(x+4)=-28
tìm x,biết:
\(\dfrac{1}{21}+\dfrac{1}{28}+\dfrac{1}{36}+........+\dfrac{2}{x\left(x+1\right)}=\dfrac{2}{9}\)
1) 3.(x-1/2)-5.(x+3/5) = -x +1/5
2) |x - 3|- 28 = 4 . (-3)2- 3.(-2)4
M.n giúp mik nhé! :))
\(\dfrac{1}{21}+\dfrac{1}{28}+\dfrac{1}{36}+...+\dfrac{1}{x.\left(x+1\right):2}=\dfrac{2}{9}\)
Tìm x
6-2(x+4)=-4
6 chia hết x
2x-15:5=-7
231-(x-6)=1339:13
(x-12):6=3 - x^2-1=3
28-x^3=1
(x+2)^3=27
81-(x-5)^2=56
x^2=9
14 chia hết x +3
Tìm x thuộc Z biết:
a)-79-9.(2x-1)^2=-160
b)-2.(-x-5)+28=20-3.(x+4)
