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(x*(x-1))/2 < 21
x^2 >= 0
2*x+7 = 0
(-5/4)*p = -10
58-(2/9) = 0
| 0=2X^2+1 | | 35x^2+25x= | | x(.15)x=20.70 | | 17-24x+69x=0 | | 28x+12-18x-16=24 | | 3x+17-17x=9x+14-14x | | H(-x)=x^4-3x^2+5 | | 4x+23+157-4x=180 | | 0.02*x=1770 | | 3x+17-17x= | | 20x+15+35x+20= | | -5/4p=-10 | | 58-2/9 | | 2/3x2/3x2/3x2/3x | | .5(6x+5)=.75(8x-4) | | -10-(-5)=-10+5 | | 9x+14-14x= | | 0+p=20 | | 4x-2=2y | | 5x-12x-6x= | | 42x^2-476x-2459=0 | | 4c=c+5 | | abs(x-6)+abs(x-7)=7 | | 49(3)= | | 2log(3x-5)=7 | | -2x+3(3x-1)=11 | | 9x^4-4y^4=0 | | abs(x+3)+abs(x+7)=7 | | log(x)1/4=-4 | | D=2(a+3)-5(b-4) | | 69-4x=21 | | 420=2(r+20) |