1/2(1-x)=k+11-x=2k+2x=-2k-13/4(x-1)-2/5(3x+2)=1/10k-3/2(x-1)15(x-1)-8(3x+2)=2k-30(x-1)15x-15-24x-16=2k-30x+3021x=2k+61x=2k/21+61/21∵两解互为相反数∴-2k-1+2k/21+61/21=0-42k-21+2k+61=0-40k+40=0k=1
