a,9x^2-16=0b,(x+5)(x-5)-(x-2)^2=7c,x^2-9+2(x+3)=0d,(x+2)^2-(x-2)(x+1)=3e,(x+3)^2-4x-12=0g,x(3-x)+(x+5)^2=4i,2x^2-5x-12=0
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