решите пожалуйста тут 1-7 вопрос...

1)
$\frac{5.6 \times 0.3}{0.8} = \frac{1.68}{0.8} = \frac{16.8}{8} = 2.1$
2)
$(\frac{1}{2} {p}^{2} {q}^{3} {)}^{4} = ( \frac{1}{2} ) ^{4} {p}^{2} \times {p}^{4} {q}^{3} \times {q}^{4} = \\ = \frac{1}{16} {p}^{8} {q}^{12}$
3)
$9x {y}^{2} \times \frac{1}{3} {x}^{2} y = 3 {x}^{3} {y}^{3}$
4)4х+55=2х-25
4х+55-2х+25=0
2х+80=0
2х=0-80
2х=-80
х=-80:2
х=-40
5)(2х-3)(3х+5)=2х*3х+5*2х-3*3х-3*5=
$= 6 {x}^{2} + 10x - 9x - 15 = \\ = 6 {x}^{2} + x - 15$
6)
$5 {a}^{5} b - 15 {a}^{4} {b}^{3} = 5 {a}^{4} b(a - 3 {b}^{2} )$
7)
$(4a + 2b) ^{2} = {(4a)}^{2} + 2 \times 4a \\ \times 2b + {(2b})^{2} = \\ 16 {a}^{2} + 16ab + 4 {b}^{2}$