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k in (-oo:+oo)
20/80 = k // - k
20/80-k = 0
1/4-k = 0 // - 1/4
-k = -1/4 // * -1
k = 1/4
k = 1/4
| 20/80= | | 0.50x+0.25(30)=38.5 | | 2+3x=6+2x | | 20/80 | | 5z-1=16 | | x^2-79x-162=0 | | 2x^2+4x+6= | | (36/144)^(1/2) | | 1200x-100=3230x-190 | | 4xsquared-8=0 | | log[3](7x-9)=log[3](2x^2) | | 11x-(7x-2)=38 | | (36/144)^1/2 | | log[3](7x-9)=log[3](4) | | (36/133)^1/2 | | 3x-5=24x-7 | | 15ab/4b^4÷5a/2b | | 3(x-6)=3x-16 | | 1200x+100=3230x-190 | | 1200x+100=3230x+190 | | 8+4v=8(1-7v)-4v | | 5y-3=3y+18 | | 11m-10=-20+12m | | 50/x=4 | | 275=15+10x | | 15-4(n-2)=27 | | 9a-9ab-6-2ab+7a= | | 32+6(z-5)=-48 | | 2(-5)(6-11)+7= | | a=-bx/2c | | -[7z-(18z+5)]=5+(10z+1) | | 2x*x+16=6x*x |