เรขาคณิตวิเคราะห์ · 2017-03-18 ·...
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เรขาคณตวเคราะห
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Ẻ½ƒ¡ËÑ ·Õè 1 (ÃÐÂÐË‹Ò§ÃÐËÇ‹Ò§¨Ø Êͧ¨Ø ) 1. ¨§ËÒÃÐÂÐÃÐËÇ‹Ò§ Ø´µ‹Í仹Õé¡Ñº Ø´¡íÒà¹Ô (0, 0)
1.1. (3, 4)
1.2. (-3, 4)
1.3. (6, 8) 2. ¨§ËÒÃÐÂзҧÃÐËÇ‹Ò§ شᵋÅФًã¹áµ‹ÅТŒÍµ‹Í仹Õé
2.1. (1, 0) áÅÐ (5, 0)
2.2. (-5, 0) áÅÐ (4, 0)
2.3. (-8, 0) áÅÐ (4, 0)
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3. ¶ŒÒÃÐÂÐË‹Ò§ÃÐËÇ‹Ò§ Ø´ (x, 3) áÅÐ (4, 7) ෋ҡѺ 5 ˹‹Ç ¨§ËÒ¤‹Ò¢Í§ x2+1 4. ¶ŒÒÃÐÂÐÃÐËÇ‹Ò§ Ø´ (1, y) ¡Ñº (7, 10) ໚¹Êͧ෋ҢͧÃÐÂÐÃÐËÇ‹Ò§ Ø´ (3, 4) áÅÐ (6,
8) áÅŒÇ ¨§ËÒ y2+1 àÁ×èÍ y ໚¹àÅ¢ËÅÑ¡à´ÕÂÇ 5. ¨§ËÒ¾Ô¡Ñ´¢Í§ P(x, 3) «Öè§Ë‹Ò§¨Ò¡ Ø´ Q(10, 12) ໚¹ÃÐÂзҧ 15 ˹‹ÇÂ
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6. ¨§ËÒ Ø´«Öè§ÍÂÙ‹º¹á¡¹ Y áÅÐÍÂÙ‹Ë‹Ò§¨Ò¡ Ø´ (2, 5) áÅÐ (3, -7) ໚¹ÃÐÂзҧ෋ҡѹ 7. Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ´ŒÒ¹à·‹Ò 2 Ø´ ¤×Í (0, 0) áÅÐ (0, 4) ¨§ËÒ¾×é¹·Õè¢Í§ÃÙ»
ÊÒÁàËÅÕèÂÁ´ŒÒ¹à·‹ÒÃÙ»¹Õé 8. ǧ¡ÅÁÃٻ˹Öè§ÁÕ Ø´ÈÙ¹Â�¡ÅÒ§·Õè Ø´ (5, 7) áÅм‹Ò¹ Ø´ (2, 11) ¨§ËÒ¤ÇÒÁÂÒǢͧÃÑÈÁÕǧ¡ÅÁ
¹Õé
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9. ¶ŒÒ Ø´ P(4, y) ÍÂÙ‹Ë‹Ò§¨Ò¡ Ø´ A(-5, 2) áÅÐ B(13, -6) ໚¹ÃÐÂзҧ෋ҡѹ ¨§ËÒ¤‹Ò y
10. §áÊ´§Ç‹Ò Ø´ (1, 1), (-1, -1) áÅÐ (-4, 1) ໚¹ Ø´ÂÍ´¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁÁØÁ©Ò¡ËÃ×ÍäÁ‹ 11. ¶ŒÒ D(-4, 2) ໚¹ شዧʋǹ¢Í§àÊŒ¹µÃ§·Õèàª×èÍÁ Ø´ A(-8, 4) áÅÐ B(2, -1) ¨§ËÒ
ÍѵÃÒʋǹẋ§¢Í§ AD:DB
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Ẻ½ƒ¡ËÑ ·Õè 2 (¨Ø ¡Ö觡ÅÒ§ÃÐËÇ‹Ò§¨Ø Êͧ¨Ø ) 1. ¨§ËÒ Ø´¡Ö觡ÅÒ§ÃÐËÇ‹Ò§ شᵋÅФًµ‹Í仹Õé
1.1. (0, 0) áÅÐ (6, 8)
1.2. (1, 2) áÅÐ (7, 6)
1.3. (-3, 4) áÅÐ (5, -6) 2. ¶ŒÒʋǹ¢Í§àÊŒ¹µÃ§ P1(x1, y1), P2(x2, y2) µÑ´á¡¹ x ·Õè Ø´ A(3, 0) áÅеѴ᡹ y ·Õè
Ø´ B(0, 4) ¶ŒÒ Ø´ A áÅÐ B ẋ§Ê‹Ç¹àÊŒ¹µÃ§ P1P2 Í͡໚¹ 3 ʋǹ෋Òæ¡Ñ¹ ¨§ËÒ P1(x1, y1) áÅÐ P2(x2, y2)
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3. ¡íÒ˹´ A(-3, 1), B(5, 7) áÅÐ C(1, 11) ໚¹ Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¨§ËÒØ´»ÅÒ¢ͧàÊŒ¹ÁѸ°ҹ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ÃÙ»¹Õé
4. ¡íÒ˹´ A(1, 4), B(2, -2) áÅÐ C(8, 4) ໚¹ Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¨§ËÒ
¤ÇÒÁÂÒǢͧàÊŒ¹ÁѸ°ҹ¢Í§ÊÒÁàËÅÕèÂÁ¹Õè·ÕèÅÒ¡¨Ò¡ Ø´ A 5. ¶ŒÒ D(0, 2) ໚¹ Ø´¡Ö觡ÅÒ§ÃÐËÇ‹Ò§ Ø´ A(-2, 1) áÅÐ C(x, y) áÅжŒÒ C(x, y) ໚¹
Ø´¡Ö觡ÅÒ§ÃÐËÇ‹Ò§ Ø´ A áÅÐ B(x1, y1) áŌǨ§ËÒ x1 + y1
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6. ¶ŒÒ O(x, 3) ໚¹ Ø´ÈÙ¹Â�¡ÅÒ§¢Í§Ç§¡ÅÁǧ˹Ö觫Öè§ÁÕ Ø´ A(-2, 0) áÅÐ B(5, 7) ÍÂÙ‹º¹àÊŒ¹Ãͺǧ¡ÅÁ¢Í§Ç§¡ÅÁ¹Õé ¨§ËÒ x
7. ¡íÒ˹´ A(-3, 5), B(4, 6) áÅÐ C(5, 5) ໚¹ Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC «Öè§
ºÃà ØÍÂÙ‹ã¹Ç§¡ÅÁ·ÕèÁÕ Ø´ÈÙ¹Â�¡ÅÒ§ÍÂÙ‹·Õè Ø´ (x, y) ¨§ËÒ Ø´ (x, y)
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8. ¡íÒ˹´ A(6, 7), B(1, 2) áÅÐ C(11, 2) ໚¹ Ø´ÂÍ´¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¨§¾×é¹·Õè¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC
9. ¡íÒ˹´ A(-2, 4), B(-2, -2) áÅÐ C(6, -2) ໚¹ Ø´ÂÍ´¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¨§
ËÒ Ø´ÈÙ¹Â�¡ÅÒ§áÅÐÃÑÈÁբͧǧ¡ÅÁ·ÕèÅŒÍÁÃͺÃÙ»ÊÒÁàËÅÕèÂÁ ABC 10. ¶ŒÒ A(3, 8), B(1, 1) áÅÐ C(7, 5) ໚¹ Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¨§ËÒ¤ÇÒÁ
ÂÒǢͧàÊŒ¹ÁѸ°ҹ·ÕèÅÒ¡¨Ò¡ÁØÁ A ÁÒÂѧ´ŒÒ¹ BC
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Ẻ½ƒ¡ËÑ ·Õè 3 (¤ÇÒÁªÑ¹¢Í§àÊŒ¹µÃ§) 1. ¨§ËÒ¤ÇÒÁªÑ¹¢Í§àÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´µ‹Í仹Õé
1.1. (0, 0) áÅÐ (3, 4)
1.2. (0, 0) áÅÐ (-5, -6)
1.3. (1, 2) áÅÐ (3, 4)
1.4. (-2, 3) áÅÐ (-4, 5)
1.5. (-3, -4) áÅÐ (5, 6)
2. ¡íÒ˹´ A(-2, -2), V(4, -2), C(x, y) áÅÐ D(-2, 2) ໚¹ Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»
ÊÕèàËÅÕèÂÁ¤Ò§ËÁÙ â´ÂÁÕ AB ໚¹°Ò¹«Öè§ÂÒÇ໚¹Êͧ෋Ңͧ¤ÇÒÁÂÒÇ CD ¨§ËÒ¤ÇÒÁªÑ¹¢Í§ BC
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3. ¨§áÊ´§Ç‹ÒàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (1, 2) áÅÐ (4, 6) ¢¹Ò¹¡ÑºàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-3, 4) áÅÐ (0, 8)
4. ¶ŒÒàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-3, -5) áÅÐ (k, -4) ¢¹Ò¹¡ÑºàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (4, 3)
áÅÐ (6, 4) ¨§ËÒ¤‹Ò k
5. ¡íÒ˹´ A(5, 6), B(-1, 2) áÅÐ C(7, 0) ໚¹ Ø´ÂÍ´¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¶ŒÒ D
áÅÐ E ໚¹ Ø´¡Ö觡ÅÒ§¢Í§´ŒÒ¹ AB áÅÐ AC ¨§áÊ´§Ç‹Ò DE ¢¹Ò¹¡Ñº BC áÅÐ DE =1
2BC
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6. ¡íÒ˹´ A(-3, -1), B(5 ,3), C(3, 5) áÅÐ D(1, 7) ໚¹ Ø´ÂÍ´¢Í§ÃÙ»ÊÕèàËÅÕèÂÁABCD ¶ŒÒ P,Q,R áÅÐ S ໚¹ Ø´¡Ö觡ÅÒ§¢Í§´ŒÒ¹ AB, BC, CD áÅÐ DA µÒÁÅíҴѺ ¨§áÊ´§Ç‹Ò PQRS ໚¹ÊÕèàËÅÕèÂÁ´ŒÒ¹¢¹Ò¹
7. ¶ŒÒ Ø´ (a, 1), (2, 3) áÅÐ (4, 7) ÍÂÙ‹º¹àÊŒ¹µÃ§à´ÕÂǡѹ ¨§ËÒ¤‹Ò a
8. ¨§áÊ´§Ç‹Ò A(-2, 3), B(4, 5), C(2,9) áÅÐ D(-1, 8) ໚¹ Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»ÊÕèàËÅÕèÂÁ
¤Ò§ËÁÙ
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9. ¨§áÊ´§Ç‹Òʋǹ¢Í§àÊŒ¹µÃ§·ÕèÅÒ¡àª×èÍÁ Ø´¡Ö觡ÅÒ§¢Í§´ŒÒ¹ 2 ´ŒÒ¹ ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁã´æ ‹ÍÁ¢¹Ò¹áÅÐÂÒÇ໚¹¤ÃÖè§Ë¹Ö觢ͧ´ŒÒ¹·ÕèàËÅ×Í
10. §áÊ´§Ç‹Òʋǹ¢Í§àÊŒ¹µÃ§·ÕèÅÒ¡àª×èÍÁ Ø´¡Ö觡ÅÒ§¢Í§´ŒÒ¹·ÕèäÁ‹¢¹Ò¹¡Ñ¹¢Í§ÃÙ»ÊÕèàËÅÕèÂÁ¤Ò§ËÁÙ‹ÍÁ
¢¹Ò¹¡Ñº´ŒÒ¹¤Ù‹¢¹Ò¹
11. ¨§ËÒ¤ÇÒÁªÑ¹¢Í§àÊŒ¹µÃ§·ÕèÅÒ¡ÁÒµÑ駩ҡ¡ÑºàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-2, 3) áÅÐ (4, -5)
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12. §áÊ´§Ç‹ÒàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (1, 3) áÅÐ (6, 5) µÑ駩ҡ¡ÑºàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-1 ,-3) áÅÐ (-3, 2)
13. ¶ŒÒàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (4, 1) áÅÐ (1, 4) µÑ駩ҡ¡ÑºàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (m, 5) áÅÐ
(-2, 6) áŌǨ§ËÒ¤‹Ò m
14. §áÊ´§Ç‹ÒàÊŒ¹·á§ÁØÁ¢Í§ÃÙ»ÊÕèàËÅÕèÂÁ ѵØÃÑÊ‹ÍÁµÑ駩ҡ¡Ñ¹
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15. ¨§áÊ´§Ç‹Ò¶ŒÒàÊŒ¹ÁѸ°ҹ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁÂÒÇ෋ҡѹÊͧàÊŒ¹áÅŒÇ ÃÙ»ÊÒÁàËÅÕèÂÁ¹Ñ鹨Ð໚¹ÊÒÁàËÅÕèÂÁ˹ŒÒ ÑèÇ
16. àÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´¡Ö觡ÅÒ§¢Í§Ê‹Ç¹¢Í§àÊŒ¹µÃ§·Õèàª×èÍÁ Ø´ (1, 2) áÅÐ (3, 4) áÅТ¹Ò¹¡Ñº
àÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-5, 4) áÅÐ (-3, 5) ÁÕÊÁ¡ÒÃàÊŒ¹µÃ§à·‹Ò¡Ñºà·‹Òã´
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17. ¡íÒ˹´ ABC ໚¹ÃÙ»ÊÒÁàËÅÕèÂÁ˹ŒÒ ÑèÇ â´ÂÁÕ BC ໚¹°Ò¹ ¶ŒÒ¾Ô¡Ñ´¢Í§ Ø´ B áÅÐ C ¤×Í (1, 9) áÅÐ (5, 1) ¨§ËÒÊÁ¡ÒÃàÊŒ¹µÃ§·Õè໚¹Ê‹Ç¹ÊÙ§¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁÃÙ»¹Õé
18. ¡íÒ˹´ A(-2, -1), B(5, -7) áÅÐ C(-3, 4) ໚¹ Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC
¨§ËÒÊÁ¡ÒÃàÊŒ¹µÃ§·Õè໚¹Ê‹Ç¹ÊÙ§¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁÃÙ»¹Õé
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Ẻ½ƒ¡ËÑ ·Õè 4 (ÊÁ¡Òâͧ¡ÃÒ¿àÊŒ¹µÃ§) 1. ¨§ºÍ¡¤ÇÒÁªÑ¹áÅÐ Ø´·ÕèàÊŒ¹µÃ§µ‹Í仹ÕéµÑ´á¡¹ x áÅР᡹ y
1) y= -45
¤ÇÒÁªÑ¹ = µÑ´á¡¹ x ·Õè Ø´ µÑ´á¡¹ y ·Õè Ø´
2) x= -5 ¤ÇÒÁªÑ¹ = µÑ´á¡¹ x ·Õè Ø´ µÑ´á¡¹ y ·Õè Ø´
3) x5+
y
3 = 1
¤ÇÒÁªÑ¹ = µÑ´á¡¹ x ·Õè Ø´ µÑ´á¡¹ y ·Õè Ø´
2. ¶ŒÒàÊŒ¹µÃ§ ax +10y = 6 ¢¹Ò¹¡ÑºàÊŒ¹µÃ§ x+2y = 8 ¨§ËÒ¤‹Ò a
3. ¶ŒÒàÊŒ¹µÃ§ 3x+by = 5 µÑ駩ҡ¡ÑºàÊŒ¹µÃ§ 5x+3y-10 = 0 ¨§ËÒ¤‹Ò b
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4. ¨§ËÒÊÁ¡ÒâͧàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (1, 2) áÅÐ (4, 3)
5. ¨§ËÒÊÁ¡ÒâͧàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (3, -4) áÅÐ (5, -6)
6. ¨§ËÒÊÁ¡ÒâͧàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (3, 4) áÅÐÁÕ¤ÇÒÁªÑ¹à·‹Ò¡Ñº 3
4
7. ¨§ËÒÊÁ¡ÒâͧàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-1, -2) áÅТ¹Ò¹¡ÑºàÊŒ¹µÃ§ 2x-3y+4 = 0
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8. ¨§ËÒÊÁ¡ÒâͧàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-2, 3) áÅТ¹Ò¹¡ÑºàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-2, 8) áÅÐ (1, 9)
9. ¨§ËÒÊÁ¡ÒâͧàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (1, 4) áÅеÑ駩ҡ¡ÑºàÊŒ¹µÃ§ 3x+4y+5 = 0
10. §ËÒÊÁ¡ÒâͧàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-4, -5) áÅеÑ駩ҡ¡ÑºàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (1, 2) áÅÐ (6, 5)
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11. ¨§ËÒÊÁ¡ÒâͧàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´µÑ´¢Í§àÊŒ¹µÃ§ x+y = 5 áÅÐ x-y = 1 áÅТ¹Ò¹¡ÑºàÊŒ¹µÃ§ 4x-5y+6 = 0
12. §ËÒÊÁ¡ÒÃàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´µÑ´¢Í§àÊŒ¹µÃ§ x+2y = 3 áÅÐ 3y-x = 2 áÅеÑ駩ҡ¡ÑºàÊŒ¹µÃ§ 5x-2y+6 = 0
13. ¡íÒ˹´ A(-1, 9), B(-2, 1) áÅÐ C(5, 6) ໚¹ Ø´ÂÍ´ÁØÁ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¨§ËÒÊÁ¡ÒÃàÊŒ¹µÃ§«Öè§à»š¹Ê‹Ç¹ÊÙ§¢Í§ÊÒÁàËÅÕèÂÁÃÙ»¹Õé·ÕèÅÒ¡¨Ò¡ Ø´ A
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14. ¡íÒ˹´ A(2, 5), B(-2, -2) áÅÐ C(4, 0) ໚¹ Ø´ÂÍ´¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¨§ËÒÊÁ¡ÒâͧàÊŒ¹ÁѸ°ҹ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ¹Õé·ÕèÅÒ¡¨Ò¡ Ø´ÂÍ´ÁØÁ A
15. ¨§ËÒÊÁ¡ÒÃàÊŒ¹µÃ§·ÕèÁÕÃÐÂÐË‹Ò§¨Ò¡ Ø´ (1, 2) áÅÐ (6, 4) ໚¹ÃÐÂÐ෋ҡѹ
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Ẻ½ƒ¡ËÑ ·Õè 5 (ÃÐÂÐË‹Ò§ÃÐËÇ‹Ò§àÊŒ¹µÃ§¡Ñº¨Ø áÅÐÃÐÂÐÃÐËÇ‹Ò§àÊŒ¹¤Ù‹¢¹Ò¹) 1. ¨§ËÒÃÐÂÐÃÐËÇ‹Ò§àÊŒ¹µÃ§¡Ñº Ø´·Õè¡íÒ˹´ãËŒµ‹Í仹Õé
1.1. 3x+4y+5 = 0 ¡Ñº Ø´ (3, 4)
1.2. 4x-3y-8 = 0 ¡Ñº Ø´ (1, 2)
1.3. 6x+8y+12 = 0 ¡Ñº Ø´ (1, -1) 2. ¨§ËÒÃÐÂÐË‹Ò§ÃÐËÇ‹Ò§àÊŒ¹¤Ù‹¢¹Ò¹µ‹Í仹Õé
2.1. 3x+4y-5 = 0 ¡Ñº 3x+4y-10 = 0
2.2. 4x-3y-10 = 0 áÅÐ 8x-6y+10 = 0
2.3. 12x+5y = 17 ¡Ñº y = -125x -
9
5
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3. ¨§ËÒÊÁ¡ÒÃàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (2, 1) áÅÐÍÂÙ‹Ë‹Ò§¨Ò¡ Ø´¡íÒà¹Ô´à»š¹ÃÐÂÐ 2 ˹‹Ç 4. ¶ŒÒàÊŒ¹µÃ§ 3x+4y-24=0 µÑ´á¡¹ x ·Õè Ø´ A áÅРѴ᡹ y ·Õè Ø´ B ¨§ËÒ Ø´ÈÙ¹Â�¡ÅÒ§
¢Í§Ç§¡ÅÁ·ÕèÅŒÍÁÃÙ»ÊÒÁàËÅÕèÂÁ OAB àÁ×èÍ O ໚¹ Ø´¡íÒà¹Ô´ 5. ¨§ËÒÊÁ¡ÒÃàÊŒ¹µÃ§«Ö觵Ñ駩ҡ¡ÑºàÊŒ¹µÃ§ 12y=5x-7 áÅÐÍÂÙ‹Ë‹Ò§¨Ò¡ Ø´ (-1, 2) ໚¹ÃÐÂÐ
෋ҡѺ 3 ˹‹ÇÂ
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6. ¶ŒÒàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ (-5, 4) µÑ´á¡¹ x áÅÐ᡹ y ·Õè Ø´ (a, 0) áÅÐ (0, b) µÒÁÅíҴѺáÅÐ ab=10 ¶ŒÒ (a, b) ÍÂً㹤ÇÍ´Ãѹµ�·Õè 1 ¨§ËÒ a+b
7. ¶ŒÒàÊŒ¹µÃ§ 4x-3y+10 = 0 ẋ§¤ÃÖè§áÅеÑ駩ҡ¡ÑºÊ‹Ç¹¢Í§àÊŒ¹µÃ§ AB ¶ŒÒ A ÁÕ¾Ô¡Ñ´ (-
4, 3) ¨§ËÒ¾Ô¡Ñ´¢Í§ Ø´ B
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8. ¶ŒÒ D(1, 5), E(2, 3) áÅÐ F(4, 6) ໚¹ Ø´¡Ö觡ÅÒ§¢Í§´ŒÒ¹ AB, BC áÅÐ CA µÒÁÅíҴѺ¢Í§ÃÙ»ÊÒÁàËÅÕèÂÁ ABC ¨§ÊÁ¡ÒÃàÊŒ¹µÃ§·ÕèÅÒ¡¼‹Ò¹ Ø´ A áÅТ¹Ò¹¡Ñº´ŒÒ¹ BC
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