Пошаговое объяснение:
49+42a+9a^2=(3a)^2+2*3a*7+7^2=(3a+7)^2
9b^2+6bc+c^2=(3b)^2+2*3bc+c^2=(3b+c)^2
49x^2-14x+1=(7x)^2-2*7x*1+1^2=(7x-1)^2
36x^2+12xy+y^2=(6x)^2+2*6xy+y^2=(6x+y)^2
Пошаговое объяснение:
49+42a+9a^2=(3a)^2+2*3a*7+7^2=(3a+7)^2
9b^2+6bc+c^2=(3b)^2+2*3bc+c^2=(3b+c)^2
49x^2-14x+1=(7x)^2-2*7x*1+1^2=(7x-1)^2
36x^2+12xy+y^2=(6x)^2+2*6xy+y^2=(6x+y)^2