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x in (-oo:+oo)
1/21 = x-(2/3) // - x-(2/3)
1/21-x+2/3 = 0
5/7-x = 0 // - 5/7
-x = -5/7 // * -1
x = 5/7
x = 5/7
| d+1=-2 | | x/2=-5/7 | | m/3=-5 | | t+2/7=92/77 | | 12=k+1 | | d/3=-5/6 | | kx^2-(2k-3)x+(k+2)=0 | | t+1/7=-6/7 | | m-9/10=-109/10 | | -7+w=4 | | -7n=-7/4 | | b/-3=4 | | 7m=63/10 | | w+5=49/9 | | 28/45=t+2/5 | | m-2/7=5/7 | | t-1/10=17/30 | | 1/6d=11/72 | | 1/6d=11/72 | | -2/9+w=25/36 | | m-7=-32/5 | | 4q-4=6q-5 | | k/-6=-6/7 | | 5/9+w=14/9 | | d/6=-1/2 | | m-3/5=-7/20 | | m/7=-3/7 | | a-1/2=-9/2 | | a+5=11 | | x+8=43/5 | | 7/9+d=43/9 | | x+9=65/7 |