Question

Resposta pfv!!!! Obs: Das duas questões!!!
a) 5x-(2x+3)²
b) (x+5)²-x(x+3)

Answer 1

a) $5x-(2x+3)^2\\=5x-(2x+3)(2x+3)\\=5x-(2x)^2+2(2x)(3) + (3)^2\\=5x-4x^2+12x+9\\=4x^2+12x+5x+9\\=4x^2+17x+9$

b) $(x+5)^2-x(x+3)\\=(x+5)(x+5)-x^2-3x\\=[(x)^2+2(x)(5)+(5)^2]-x^2-3x\\=x^2 + 10x + 25 - x^2 - 3x\\=x^2 - x^2 + 10x - 3x + 25\\=7x + 25$