Question

giải phương trình

a. 3-2=2x-3                          b.2x+3=5x                      c. 5-2x=7                              d . 10x+3-5x=4x+12          

e.11x+42-2x=100-9x-22         f. 2x-(3-5x)=4(x+3)                      g,x(x+2)=x(x+3)           

Answer 1

a/ 3 - 2 = 2x - 3

<=> -2x = -3 +2 - 3 

<=> -2x = -4

<=> x= 2 

b/ 2x + 3 = 5x

<=> 2x - 5x = -3

<=> -3x = -3

<=> x=1 

c/ 5 - 2x= 7

<=> -2x = 7-5

<=> -2x = 2

<=> x+ -1

d/ 10x + 3 - 5x = 4x+12

<=> 10x -5x - 4x= 12-3

<=> x = 9

e/ 11x + 42  - 2x = 100 - 9x - 22

<=> 11x - 2x + 9x = 100-22-42

<=> 18x = 36 

<=> x = 2

f/  2x - ( 3- 5x) = 4(x+3)

<=> 2x - 3 + 5x = 4x + 12

<=> 2x + 5x - 4x = 12 + 3

<=> 3x = 15

<=> x = 5

g/ x(x+2) = x(x+3)

<=>x² +2x = x² + 3x

<=>x² - x² +2x - 3x= 0

<=> -x= 0 

<=> x= 0