Question

Tìm số tự nhiên  x, y  biết:

a) (x-1). (y+1) =6

b) (2x-1). (2y+1) =9

Answer 1

a)

(x+x).(1-1)=6

2x.0=6

2x=6:0

2x=0

x=0:2

x=0

b)

(2x+2x).(1-1)=9

4x.0=9

4x=9:0

4x=0

x=0:4

x=0

 

Answer 2

Tìm x, y biết:

a) (x-1). (y+1) =6

(x - 1) = 6 hoac (y + 1) = 6

x    = 6+1   ;      y   = 6-1

x    =  7    ; y   =  5

Vay x=7 hoac x=5

b) (2x-1). (2y+1) =9

(2x-1) = 9  hoac (2y+1) =9

2x      = 9+1 hoac 2y    =9-1

2x     = 10   hoac 2y    = 8

  x     = 10 : 2  hoac y   = 8 : 2

  x     = 5        hoac y   = 4

Vay x=5 ; y=4

Answer 3

a)(x-1)(y+1)=6

x-1	1	2	3	6
x	2	3	4	7
y+1	6	3	2	1
y	5	2	1	0

b)(2x-1)(2y+1)=9

2x-1	1	3	9
2x	2	4	10
x	1	2	5
2y+1	9	3	1
2y	8	2	0
y	4	1	0