To solve the equation. 7x + 0.7 × 8 = 20.6 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X - (521 + 37) = 23

To solve the equation. 7x + 0.7 × 8 = 20.6 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; X - (521 + 37) = 23

（1）7x+0.7×8=20.6       7x+5.6-5.6=20.6-5.6            7x÷7=15÷7                x=217；（2）x-（521+37）=23            x-23=23         x-23+23=23+23              x=113．

The equation (3a + 5x) / 6 = A / 4-7x / 4 of X has the same solution as equation 4 (3x-7) = 19-35x to find the value of - 3A + 4
Finding the value of a

By solving the first equation, we get x = - 3A / 31; by solving the second equation, we get x = 1, so 1 = - 3A / 31. A = - 31 / 3
So the original formula is 35

We know the equation 4 (x-3) + 2A = - x + 5 ①；7x-3＝a+x…… ② If the ratio of the roots of equation 1 to equation 2 is 6:5, try to find the value of A

Because 4 (x-3) + 2A = - x + 5, so 5x = 17-2a, so x = (17-2a) / 5
Because 7x-3 = a + X, 6x = a + 3, so x = (a + 3) / 6
So (17-2a) / 5: (a + 3) / 6 = 6:5
Then work out a

If the root ratio of equation (1) to equation (2) is 6:5, try to find the value of A

4（x-3)+2a=-x+5.①
7x-3=a+x.,②
By simplifying (1), we get x = (17-2a) / 5
Simplify 2, get x = (a + 3) / 6
According to the meaning of the title
(17-2a)/5÷（a+3）/6=6÷5
A = 14 / 3