Resposta:
2)a) 18x
b) +25
c)x^2
d)x^2
3) D
Explicação passo-a-passo:
2) a) (x+9)^2=x^2+2×x×9+9^2=x^2+18x+81
b) (×-5)^2=x^2-2×x×5+5^2=x^2-10x+25
c) (x-6)^2=x^2-2×x×6+6^2=x^2-12x+36
d) (x+4)^2=x^2+2×x×4+4^2=x^2+8x+16
3)(2x+10)^2=(2x)^2+2×(2x)×10+10^2=4x^2+40x+100
