\(6x+4x=2010\)

\(x\cdot\left(6+4\right)=2010\)

\(x\cdot10=2010\)

\(x=2010\div10\)

\(x=201\)

6x + 4x = 2010

10x = 2010

x = 2010 : 10

x = 201

\(6x+4x-2x=2010\)

\(10x-2x=2010\)

\(8x=2010\)

\(\Rightarrow x=\frac{1005}{4}=251,25\)

6x + 4x - 2x = 2010

= 10x - 2x = 2010

8x = 2010

= > x = 1005/4 = 251,25

Ps: Câu này dễ mà Do Not Ask Why cũng trả lời ! Tôi là học sinh lớp năm mà còn biết trả lời đây!

a) 8x = 2010

x = 251.25

b) x(y-2) = 0

x = 0 hay y - 2 = 0

x = 0 hay y = 2

a) \(\left(x-10\right).11=0\Rightarrow x-10=0\Rightarrow x=10\)

b) \(6x+4x=2010\Rightarrow10x=2010\Rightarrow x=201\)

a)[x-10].11=0

   [x-10]     =0:11

   [x-10]     =0

    x           =0+10

    x           =10

b)6x + 4x = 2010

   x . (6+4)=2010

   x . 10    =2010

   x           =2010:10

   x           =201

Giải:

a) \(6x+4x=2010\)

\(\Leftrightarrow10x=2010\)

\(\Leftrightarrow x=\dfrac{2010}{10}\)

\(\Leftrightarrow x=201\)

b) \(1+2+...+x=45\)

\(\Leftrightarrow\dfrac{\left(x+1\right).x}{2}=45\)

\(\Leftrightarrow\left(x+1\right).x=90\)

Mà \(90=9.10\)

\(\Leftrightarrow x=9\)

c) \(1+3+5+...+x=36\)

\(\Leftrightarrow\dfrac{\left[\left(x-1\right):2+1\right].\left(x+1\right)}{2}=36\)

\(\Leftrightarrow\left[\left(x-1\right):2+1\right].\left(x+1\right)=72\)

\(\Leftrightarrow\left[\left(x-1\right).\dfrac{1}{2}+1\right].\left(x+1\right)=72\)

\(\Leftrightarrow\left(\dfrac{1}{2}x-\dfrac{1}{2}+1\right).\left(x+1\right)=72\)

Mà \(72=6.12\)

\(\Leftrightarrow x=11\)

Chúc bạn học tốt!

a) 6x + 4x = 2010

=

=

b)1 + 2 + .. + x = 45

=> x = 45 - (1 + 2 + ...)

x = 45 - 3 = 42

c) 1+ 3 + 5 + ... + x = 36

=> x = 36 - (1 + 3 + 5)

x= 36 - 9

27

Đs:

P: Câu a mình không biết nên bạn thông cảm

Ta có:

a)\(25< 2^x< 3125\)

\(\Rightarrow2^4< 2^x< 2^{12}\)

\(\Rightarrow4< x< 12\)

b)\(\left(x+1\right)+\left(x+2\right)+...+\left(x+100\right)=7450\)

\(\Rightarrow100x+5050=7450\Rightarrow10x=2400\Rightarrow x=240\)

c)\(1+2+3+..+x=\frac{x\left(x+1\right)}{2}=78.\)

\(\Rightarrow x\left(x+1\right)=156\)\(\Rightarrow x=12\)

d)\(12x+13x=25x=2000\Rightarrow x=80\)

e)\(6x+4x=10x=2010\Rightarrow x=201\)