<span>16m^2-100n^2-(16m^2-8mn+n^2)= 16m^2-100n^2-16m^2+8mn-n^2=-101n^2+8mn, вроде так</span>
5(x-3)=14-2(7-2x)
5x-15=14-14+4x
x=15
- 5 + 9x = 10x + 4
10x - 9x = - 5 - 4
X = - 9
Вроде так)
y-3y+8+9-6y=-8y+17
8-2y+1+5-6y+8=-8y+22
А) 250+ 90*12 =1330
Б) 225+ 13* 75 = 1200
В) 200+200+ 80*12= 1360