Question

Îmi trebuie urgent toate exerciţiile

Answer 1

1)25t^2-30t+9=(5t-3)^2
2)a) (3a-7)-(4-a)=3a-7-4+a=4a-1
b)-0,5a(4+2a)=-2a-1a=-3a
c)(3x+2)^3=9x^3+3*9x^2*2+3*3x*4+8=9x^3+54x^2+24x+8
3)a)3x^2+9xy=3x(x+3y)
b)x^2-49=(x+7)*(x-7)
c)ax-ay+5x-5y=(ax+5x)+(-ay-5y)=x(a+5)-y(a-5)=(x-y)(a^2-25)
d)25x^-10xy+y^2=(5x-y)^2
4)a)(a-9)^2-(8+2a)=a^2-18a+81-8+2a=a^2-16a+73
5)(7-2√3)(7+2√3)=49-12=37cm^2