Toán 8 nè dễ lắm !!

Question

Tìm x, bt

A, 2.(5x - 8 ) - 3.( 4x - 5 ) = 4.( 3x - 4 ) + 11

B, x.( 2x - 3 ) + 3x. ( x + 5 ) = 5x. ( x - 3 ) + 4. ( x - 2 ) 

C, 5x - 2 .{ x - 4 [ x + 2 ( x- 3 ) ] } = 0

D, 5x. ( x - 3 ) + 2. ( 3 - 2x ) = 5x^2 -  4 . ( x + 5)

Nhân đơn thức vs đa thức 

Comments

toán mấy vậy bn 

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toan 8 nha bn

Answer 1

a, 2(5x - 8) - 3(4x - 5) = 4( 3x - 4) + 11

<=>10x - 16 - 12x + 15 = 12x - 16 + 11

<=> 10x - 12x - 12x = -16 + 11 + 16 - 15

<=> -14x = -4

b, x( 2x - 3) + 3x( x + 5) = 5x( x - 3) + 4( x - 2)

c, 5x - 2{ x - 4[ x + 2( x - 3)]} = 0

d, 5x( x - 3) + 2( 3 - 2x) = 5x^2 - 4( x + 5)

Answer 2

mk vừa trl lúc nãy ^_^ :lop67.tk/hoidap/236386/toán-8-nè-dễ-lắm