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(3x+8)(4x-2)-(7x-4)(3-9x) 12х²-6х+32х-16-(21х-56х²-12+36х) = 12х²-6х+32х-16-21х+56х²+12-36х= 68х² -31х -4 = 68•2+31•2-4 = 136+62-4= 132+62= 194
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