x *6+ ( 1 + 2 + 3 + 4 + 5 ) = 45

x*6=45-15=30

x=30:6=5

ủng hộ nha các bạn

khong phai toan lop 3

=> ( x + x + x + x + x + x ) + ( 1 + 2 + 3 + 4 + 5 ) = 45

=> 6x + 15 = 45

=> 6x = 45 - 15 = 30

=> x = 30 : 5 = 5

Vậy x = 5

x+1 + x+2 + x+3 + x +4 + x+5 = 45

x + x + x + x + x = 45 -1 -2 -3 -4 -5

5x = 30

x =6

(x+1)+(x+2)+(x+3)+(x+4)+(x+5)=45 

(x + x + x + x + x) + ( 1 + 2 + 3 + 4 + 5)  = 45

\(x\times5\)+ 15 = 45

\(x\times5\)       = 45 - 15

\(x\times5\)        = 30

x                      = 30 : 5

x                      = 6.

Hok tốt !

1) x = 4/5 - 1/3

x = 7/15

2) 5/3.x=1/21

x=1/35

3) -12/13.x = 1/13

x=-1/12

7) th1: x-1=2/3

x = 5/3

Th2: x - 1 = -2/3

x=1/3

5x+15=45

5x=35

x=7

(x+1)+(x+2)+(x+3)+(x+4)+(x+5)=45

( x + x + x + x + x ) + ( 1 + 2 + 3 + 4 + 5 ) = 45

5x + 15 = 45

5x = 45 - 15

5x = 30

x = 30 : 5

x = 6

(x+1)+(x+2)+(x+3)+(x+4)+(x+5)=45

(x + x + x + x + x)+(1 + 2 + 3 + 4 + 5) = 45

5x + 15 = 45

5x =45 - 15

5x = 30

x=30:6

x=5

\(\frac{2}{3}x\frac{4}{y}=\frac{4}{45}:\frac{1}{5}\)\(=\frac{4}{15}\)

\(\frac{4}{y}=\frac{4}{15}:\frac{2}{3}\)\(=\frac{2}{5}\)

y=4:\(\frac{2}{5}\)    y=10

\(\frac{3}{4}x\frac{y}{5}=\frac{15}{4}\)

\(\frac{y}{5}=\frac{15}{4}:\frac{3}{4}=5\)

y=5x5=25

Câu hỏi tương tự nha !!!!!

(x + 1) + (x + 2) + (x + 3) + (x + 4) + (x + 5) = 45

x + 1 + x + 2 + x + 3 + x + 4 + x + 5 = 45

(x + x + x + x + x) + (1 + 2 + 3 + 4 + 5) = 45

5x + 15 = 45

5x = 45 - 15

5x = 30

x = 6