X+X/5 x 15/2+X/2.9=315

=>X+3X/2+9X/2=315

=>X+12X/2=315

=>X+6X=315=>7X=315=>X=45

càm ơn 

a) \(\frac{2}{3}:\frac{2}{3}\times x=1\)

\(1\times x=1\)

x = 1

b) \(x+x:5\times7,5+x:2\times9=315\)

\(x+x\cdot\frac{1}{5}\cdot7,5+x\cdot\frac{1}{2}\cdot9=315\)

\(x\cdot\left(1+\frac{1}{5}.7,5+\frac{1}{2}.9\right)=315\)

x.7 = 315

x = 45

Dấu . là dấu nhân nha

Tìm x : 

a) 2/3 : 2/3 × X = 1 

1 × X = 1 

X = 1 : 1 

X = 1 

b) X + X : 5 × 7,5 + X : 2 × 9 = 315

X + X × 1/5 × 7,5 + X × 1/2 × 9 = 315 

X × 1 + X × 1,5 + X × 4,5 = 315 

X × ( 1 + 1,5 + 4,5 ) = 315 

X × 7 = 315 

X = 315 : 7

X = 45

VẬY X = 45

 x+x:5*7,5+x:2 *9=315

x*1+x*1,5+x*4,5=315

x*[1 +2,5+4,5]=315

x*7=315

x =315:7

x=45

x + x:5x7,5 + x : 2x9 = 315

x + x:37,5 + x   :18   = 315

x + (37,5 + 18 )        = 315

x +  55,5                 = 315

          x                  = 315 - 55,5

          x                  = 259,5

jaki natsumi

x+x:5x7,5+x:2x9 = 315

x+x:37,5  +x:18   = 315

x : ( 37,5 +18 +1) = 315

x :56,5                = 315

x                        = 315 x 56,5 

x                        = 17 797,5

\(x+x\div5\times\frac{15}{2}+x\div2\times9\)

\(x+\frac{x}{5}\times\frac{15}{2}+\frac{x}{2}\times9=315\)

\(\Leftrightarrow x+\frac{3x}{2}+\frac{9x}{2}=315\)

\(\Leftrightarrow7x=315\Rightarrow x=45\)

X + X : 5 x 7,5 + X : 2 x 9 = 315

X + X x 1,5 + X x 4,5        = 315

X x ( 1 + 1 , 5 + 4,5 )       = 315

X x 7                               = 315

X                                     = 45

X+X:5x7,5+X:2x9=315

X+Xx1,5+Xx4,5=315

Xx7                 =315

X                    =45

xchxj u 45623

Tìm x, biết:
x + x/5 . 7,5 + x/2 . 9 = 315
=> x + (7,5/5).x + (9/2).x = 315
=> x + 1,5x + 4,5x = 315
=> x.(1 + 1,5 + 4,5) = 315
=> x.7 = 315
=> x = 315/7
=> x = 45
Vậy x = 45

hahahaha

hình như x = 45

\(x+x:5.7,5+x:2.9=315\)

\(x+x.1,5+x.4,5=315\)

\(x.\left(1+1,5+4,5\right)=315\)

\(x.7=315\)

\(x=315:7=45\)

x + x : 5 . 7,5 + x : 2 . 9 = 315

x + x : 37,5 + x : 18 = 315

x + x . 2/75 + x . 1/18 = 315

x ( 1 + 2/75 + 1/18 ) = 315

x . 487/450 = 315

x = 141750/487