Resposta :
a) (x+5)(x+2)=[tex] x^{2} +2x+5x+10= x^{2} +7x+10[/tex]
b) [tex](3x+2)(2x+1)=6 x^{2} +3x+4x+2=6 x^{2} +7x+2[/tex]
c) [tex](5x-2)(2x-1)= x^{2} -5x-4x+2=10 x^{2} -9x+2[/tex]
b) [tex](3x+2)(2x+1)=6 x^{2} +3x+4x+2=6 x^{2} +7x+2[/tex]
c) [tex](5x-2)(2x-1)= x^{2} -5x-4x+2=10 x^{2} -9x+2[/tex]