Question

Tìm x

28 + ( 2 x — 3 ) = 45

167+3. (15 — x ) = 170

233 — 9 x = 5⁴ : 5

Answer 1

1 ) 28 + ( 2x - 3 ) = 45

=> 2x - 3 = 17

=> 2x     = 20

=> x = 10

2) 167 + 3 ( 15 - x ) =170

=> 3 ( 15 - x ) = 3

=> 15 - x  = 1

=> x = 14

3 ) 233 - 9x = 5⁴ : 5 

=> 233 - 9x = 5³

=> 9x = 233 - 5³ 

=> 9x = 108

=> x =12 

Answer 2

28 + [ 2x - 3 ] = 45

2x - 3 = 45 - 28

2x - 3 = 17

2x = 17 + 3

2x = 20

x = 20 : 2

x = 10

167 + 3 . [15 - x ] = 170

3.[15-x] = 170 - 167

3.[15-x] = 33

15 -x = 33 : 3

15 - x = 11

    x = 15 -11

x =4

^{233 - 9 . x = 125}

^{9 . x = 233 - 125}

^{9 . x =108}

^{x = 108 : 9}

^{x = 12}