標題:
幫幫我 ,, 數學 ,,,,急急急急!!!
發問:
1 ) 9k-1=-6k-31 2 ) 10-5x=1-x+1+2x 3 ) 0.4a-0.2(a-6)=0.5 4 ) 5[2(y-4.2)+y-1]=y-5 5 )19-7b-5b=-53 6 ) 2(2x-1)=6 7 ) 3(2-z)=-9 8 ) 16=-8(5p+8) 9 ) 5(7+3q)+12=2 十萬火急 !!! 要有過程 ,, 用天平方式計 ,,
最佳解答:
1 ) 9k – 1 = - 6k – 31 9k + 6k = 1 – 31 15k = - 30 ∴ k = - 2 2 ) 10 - 5x = 1 – x + 1 + 2x 10 - 5x = 2 + x 10 – 2 = x + 5x 6x = 8 x = 8/6 ∴ x = 4/3 3 ) 0.4a - 0.2 (a - 6) = 0.5 0.4a - 0.2 a + 1.2 = 0.5 0.2 a + 1.2 = 0.5 0.2 a = 0.5 – 1.2 0.2 a = - 0.7 a = (- 0.7) / 0.2 ∴ a = - (7/2) 4 ) 5[2(y - 4.2) + y - 1] = y - 5 5[2y – 8.4 + y - 1] = y - 5 5(3y – 9.4) = y - 5 15y – 47 = y – 5 15y – y = 47 – 5 14y = 42 ∴ y = 3 5 ) 19 - 7b - 5b = - 53 19 - 12b = - 53 19 + 53 = 12b 12b = 72 ∴ b = 6 6 ) 2(2x - 1) = 6 4x - 2 = 6 4x = 6 + 2 4x = 8 ∴ x = 2 7 ) 3(2 - z) = - 9 6 - 3z = - 9 6 + 9 = 3z 3z = 15 ∴ z = 5 8 ) 16 = - 8 (5p + 8) 16 = - 40p – 64 64 + 16 = - 40p 80 = - 40p - 40p = 80 ∴ p = - 2 9 ) 5(7 + 3q) + 12 = 2 35 + 15q + 12 = 2 15q + 47 = 2 15q = 2 – 47 15q = – 45 ∴ q = - 3 希望幫到您！
其他解答:
此文章來自奇摩知識+如有不便請留言告知
1) 9k-1=6k-31 3k=-30 k=-10 2) 10-5x=1-x+1+2x -6x=-8 x=4/3 3) 0.4a-0.2(a-6)=0.5 0.4a-0.2a+1.2=0.5 0.2a=-0.7 a=-3.5 4) 5[2(y-4.2)+y-1]=y-5 5(2y-8.4+y-1]=y-5 5(3y-9.4)=y-5 15y-47=y-5 14y=42 y=3 5) 19-7b-5b=-53 -12b=-72 b=6 6) 2(2x-1)=6 4x-2=6 4x=8 x=2 7) 3(2-z)=-9 6-3z=-9 -3z=-15 z=5 8) 16=-8(5p+8) 16=-40p-64 80=-40p p=-2 9) 5(7+3q)+12=2 35+15q+12=2 15p=-45 p=-3
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