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a.(2x+1)²+(2-x)² = (4x²+4x +1)+ (4 - 4x +x²) = 4x² +4x +1 +4 -4x +x² = 5x² +5
b.(3x+4)(3x-4)-16 =9x² -16 -16 = 9x² - 32
a.(2x+1)²+(2-x)² = (4x²+4x +1)+ (4 - 4x +x²) = 4x² +4x +1 +4 -4x +x² = 5x² +5
b.(3x+4)(3x-4)-16 =9x² -16 -16 = 9x² - 32