b)7 –(2x + 4) = -(x + 4) c)4(3x –2 ) –3( x –4 ) = 7x + 10 d)–x2–12x + 21 = (3 –x )(x + 11) e)9x + 5x2 + 1 = 5x2–22 + 13x help me plz

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