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1/21 = 28/x
(3/8)*x = 1/3
1/21 = 28/x
735;438
1000/4 = 7/x
| 66=0.8x+72 | | -5(1+k)=-5 | | 3/8x=1/3 | | 9x=5(x-8) | | 27-v=247 | | Y-13.7=24.8 | | 10=-4x+30 | | -9=4w+7 | | 4x=9y+sY | | 1/21=28/x | | 2x-5(x-5)=-9+5x-22 | | 16b^4-81=0 | | 4y-30=-3(y+3) | | 1000/4=7/x | | 9x+8y=18 | | 4/6x1/3 | | 35=19+x | | 2x+y+3=3+5y-x | | 22=-6(x-4)-2 | | 15/12=x/4 | | 9/x=0.75 | | 3x-2+6x+3=x | | k(5)=6(5)+100 | | 2(4x-3)=4+7x | | x/9=64/72 | | 2x-5=8-x | | 7x^2+0.5x=0.01 | | K-5=-7 | | 5b=b-6 | | bx+by=z | | 3x+y-2z=-2 | | 255/420 |