Question

упростите выражение

(х-5)^2-4(х+5)^2

Answer 1

(x-5)²-4(x+5)²=x²-10x+25-4(x²+10x+25)=x²-10x+25-4x²-40x-100=-3x²-50x-75.

Answer 2

x^2 - 10x+25-4*(x^2 +10x+25)=x^2 - 10x+25-4x^2 - 40x-100=-3x^2 - 50x-75
3x^2 +50x+75
D=250-4*3*75=250-900=-650