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x - 4 (-4x) ÷ x = -4
2
x + 1 x - 3x - 4
2
x + x
- 4x - 4

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¢m¢¶ŠË³š¨šÁ¬n¬³¤–m®¿¦n¨ Š·‰¬£¹•ƒ³¤¬³¤
x - 4 Thinking Time
2
x + 1 x - 3x - 4
2
x + x 0 ÷ (x ¢¶¦¬³¤¾˜m³ƒ²›
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- 4x - 4

- 4x - 4 (x + 1) × (-4) = -4x - 4
0 (-4x - 4) - (-4x - 4) = 0

2
•²‰š²Çš x - 3x ¬³¤•n¨£ x •n¦¬³¤¾˜m³ƒ²› x –®›

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1) x + 6 - 5x ¬³¤•n¨£ x - 2
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2) x + 2x ¬³¤•n¨£ x + 5

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Š³ƒƒ³¤¬³¤Ÿ¬¹š³¢Áš–²¨®£m³‰˜¶Æ Š±¾¬Åš¨m³ ƒ³¤¬³¤ x - 4 - 3x •n¨£ x + 1
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•n¦¬³¤¾œ|š x ¿¦±Â¢m¢¶¾©ª¾¬¦¸® ¬¤¸®¢¶¾©ª¾œ|š ƒ¦m³¨Â•n¨m³ ƒ³¤¬³¤ x - 4 - 3x
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2
x - 4 - 3x = (x + 1)(x - 4)

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