Question

Giúp em bài toán lớp 7 này với: 1) \(\frac{3-2x}{5}\)= \(\frac{-2x+1}{3}\)  ;    2) \(\frac{x-1}{x-5}\)= \(\frac{6}{7}\)

Answer 1

\(\frac{3-2x}{5}=\frac{-2x+1}{3}\)

=> 5.(-2x+1) = 3.(3-2x)

=> -10x + 5 = 9 - 6x

=> -4x + 5 = 9

=> -4x = 4

=> x = -1

\(\frac{x-1}{x-5}=\frac{6}{7}\)

=> 7.(x-1) = 6.(x-5)

=> 7x-7 = 6x-30

=> 7 = x - 30

=> x = 37

Answer 2

1, => 3( 3 - 2x ) = 5( -2x + 1 ) 

 => 9 - 6x = -10x + 5

 => ( 9 - 6x ) - ( -10x + 5 ) = 0

 => 9 - 6x + 10x - 5 = 0

 => ( 9 - 5 ) + ( 6x - 10x ) = 0

 => 4 + x( 6 - 10 ) = 0

      4 + -4x = 0

=> x = 1 

hihih chắc z ^^