Упр.704 ГДЗ Мерзляк Полонский 7 класс (Алгебра)

1) 3х2 + 12ху;
2) 10m5 — 5m;
3) ab — ас + 7b — 7с;
4) 6х — ху -6у + у2;
5) 49b2 — с2;
6) р2 + 12pk + 36k2;
7) 100а4 — 1/9*b2
8) 25а2 — (а — 3)2.

1) $$3x^2+12xy=3x(x+4y).$$

2) $$10m^5-5m=5m(2m^4-1).$$

3) $$ab-ac+7b-7c=a(b-c)+7(b-c)=(b-c)(a+7).$$

4) $$6x-xy-6y+y^2=6(x-y)-y(x-y)=(x-y)(6-y).$$

5) $$49b^2-c^2=(7b-c)(7b+c).$$

6) $$p^2+12pk+36k^2=(p+6k)^2.$$

7) $$100a^4-\frac{1}{9}b^2=\left(10a^2-\frac{1}{3}b\right)\left(10a^2+\frac{1}{3}b\right).$$

8) $$25a^2-(a-3)^2=(5a-(a-3))(5a+(a-3))=(4a+3)(6a-3)=3(4a+3)(2a-1).$$

Ответ: $$ (a-b)^2=(b-a)^2; $$ 1) $$3x(x+4y);$$ 2) $$5m(2m^4-1);$$ 3) $$(b-c)(a+7);$$ 4) $$(x-y)(6-y);$$ 5) $$(7b-c)(7b+c);$$ 6) $$(p+6k)^2;$$ 7) $$\left(10a^2-\frac{1}{3}b\right)\left(10a^2+\frac{1}{3}b\right);$$ 8) $$3(4a+3)(2a-1).$$