六條中一程度的分數代數加減題目?(明日要交,急)十分【高手請進】

1、5∕2y+1=3-y
所有項目乘2, 得 5/2y * 2 + 1 * 2 = 3 * 2 - y * 2
5y + 2 = 6 - 2y
5y + 2y = 6 - 2
7y = 4
7 = 4/7

2、8x+2/3x-7=6
所有項目乘3, 得 8x * 3 + 2/3x * 3 - 7 * 3 = 6 * 3
24x + 2x - 21 = 18
26x = 18 + 21
26x = 39
x = 39/26
x = 1 1/2

3、4/3y=1-2/1y
所有項目乘3, 得 4/3y * 3 = 1 * 3 - 2/1y * 3
4y = 3 - 6y
4y + 6y = 3
10y = 3
y = 3/10

4、3/r+6=2/r+6/7
所有項目乘7r, 得 3/r * 7r + 6 * 7r = 2/r * 7r + 6/7 * 7r
21 + 42r = 14 + 6r
42r - 6r = 14 - 21
36r = -7
r = - 7/36

5、9/1(h+9)=6/5-2/1(h+7)
9/h + 81 = 6/5 - 2/h - 14
所有項目乘5h, 得 9/h * 5h + 81 * 5h = 6/5 * 5h - 2/h * 5h - 14 * 5h
45 + 405h = 6h - 10 - 70h
405h - 6h + 70h = -10 - 45
469h = -55
h = - 55/469

6、4/5t+3=4/3t
所有項目乘15t, 得 4/5t * 15t + 3 * 15t = 4/3t * 15t
12 + 45t = 20
45t = 20 - 12
45t = 8
t = 8/45

2.5Y+1=3-Y
2.5Y+Y=2
3.5Y=2
Y=0.5714