450:[41-(2x-5)]=3 mũ 2 . 5 (5x-39).7+3=80 15.5. (x-35)-525=0 [3.(70-x)+5]:2=46

0 bình luận về “450:[41-(2x-5)]=3 mũ 2 . 5 (5x-39).7+3=80 15.5. (x-35)-525=0 [3.(70-x)+5]:2=46”

1. Đáp án:

    

   Giải thích các bước giải:

    450 : [41 – (2x – 5)] =3^2.5
    450 : [41 – 2x + 5] = 9 . 5
    450 : [46 – 2x] = 45
    46 – 2x = 10
    2x = 36
     x = 18

   (5x – 39) . 7 + 3 = 80
    (5x – 39) . 7 = 77
    5x – 39 = 11
    5x = 50
      x = 10

   15.5. (x-35)-525=0

   75(x-35)=525
    x-35=7
    x=42

   3(70-x)+5=92
   3(70-x)=87
   70-x=29
   x=41

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2. +, 450 : [41 – (2x – 5)] = $3^{2}$ . 5

   ⇔ 450 : [41 – 2x + 5] = 9 . 5

   ⇔ 450 : [46 – 2x] = 45

   ⇔ 46 – 2x = 10

   ⇔ 2x = 36

   ⇔ x = 18

   +, (5x – 39) . 7 + 3 = 80

   ⇔ (5x – 39) . 7 = 77

   ⇔ 5x – 39 = 11

   ⇔ 5x = 50

   ⇔ x = 10

   +, 15 . 5 . (x – 35) – 525 = 0

   ⇔ 75 . (x – 35) = 525

   ⇔ x – 35 = 7

   ⇔ x = 42

   +, [3 .(70 – x) + 5] : 2 = 46

   ⇔ 3 .(70 – x) + 5 = 92

   ⇔ 3 .(70 – x) = 87

   ⇔ 70 – x = 29

   ⇔ x = 41

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