1) 2t/5 + t/7 = 57
2) 1/7x - 4/7 = 2/7
The / is a fraction.
* Showing the steps would be the most helpful.
How do I solve this problem?
2008-02-22 5:43 pm
回答 (4)
2008-02-22 5:47 pm
✔ 最佳答案
(2t/5) + (t/7) = 57(14t/35) + (5t/35) = 57
(14t+5t)/35 = 57
19t = 57*35
19t = 1995
t = 1995/19
t = 105
Second one:
1/7x - 4/7 = 2/7
x/7 - 4/7 = 2/7
(x-4)/7 = 2/7
x-4 = 2
x = 6
2008-02-23 1:49 am
1)
2t/5 + t/7 = 57
14t/35 + 5t/35 = 57
19t = 35(57)
t = 1995/19
t = 105
2)
1/7x - 4/7 = 2/7
1/7x = 2/7 + 4/7
1/7x = 6/7
7/7x = 6
7 = 42x
x = 7/42
x = 1/6
2t/5 + t/7 = 57
14t/35 + 5t/35 = 57
19t = 35(57)
t = 1995/19
t = 105
2)
1/7x - 4/7 = 2/7
1/7x = 2/7 + 4/7
1/7x = 6/7
7/7x = 6
7 = 42x
x = 7/42
x = 1/6
2008-02-23 1:48 am
1) 2t/5 + t/7 = 57
Multiply everything by the LCM of the denominators to eliminate them (in this case, 35)
14t + 5t = 1995
19t = 1995
t = 105
2) Same thing, but the LCM here is 7x:
1/(7x) - 4/7 = 2/7
1 - 4x = 2x
1 = 6x
x = 1/6
Multiply everything by the LCM of the denominators to eliminate them (in this case, 35)
14t + 5t = 1995
19t = 1995
t = 105
2) Same thing, but the LCM here is 7x:
1/(7x) - 4/7 = 2/7
1 - 4x = 2x
1 = 6x
x = 1/6
2008-02-23 1:47 am
1) 2t/5 + t/7 = 57
find a common denominator which is 35:
14t/35 + 5t/35 = 1995/35
multiply everything by 35:
14t + 5t = 1995
19t = 1995
t = 105
2. They already have common denominators, so multiply everything by 7:
x - 4 = 2
x = 6
find a common denominator which is 35:
14t/35 + 5t/35 = 1995/35
multiply everything by 35:
14t + 5t = 1995
19t = 1995
t = 105
2. They already have common denominators, so multiply everything by 7:
x - 4 = 2
x = 6
收錄日期: 2021-05-01 10:07:11
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