Question

Помогите пожалуйста решить эти примеры.
Даю 40 баллов..

Answer 1

$1) m^{2} +(2-m)^{2} =m^{2} +4-4m+m^{2} = 2m^{2} +4-4m$

$2) (5x-3)^{2} +30x=25x^{2} -30x+9+30x=25x^{2} +9$

$3) c^{2} +25-(c-5)^{2} =c^{2} +25-(c^{2} -10c+25)=c^{2} +25-c^{2} +10c-25=10c$

$4) 3a(a+2)-(a-1)^{2} =3a^{2} +6a-(a^{2} -2a+1)=3a^{2} +6a-a^{2} +2a-1=2a^{2} +8a-1$

$5) (y-4)^{2} -(y-3)(y+3)= y^{2} -8y+16-(y^{2} -9)=y^{2} -8y+16-y^{2} +9=-8y+25$

$6) (2x-7)^{2} -(2x-3)(2x+3)=4x^{2} -28x+49-(4x^{2} -9)=4x^{2} -28x+49-4x^{2} +9=-28x+58$