Question

срочно!помогите пожалуйста!дам 30 баллов
номер 17.4
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Answer 1

17.4

1)

$0.07a^{8}b^{4}:a^{7}+0.03a^{2}b^{6}:(ab^{2})=0.07ab^{4}+0.03ab^{4}=0.1ab^{4}=0.1*7*(-2)^{4}=\\\\=0.7*16=11.2$

2)

$2.5x^{4}y:x^{5}-2.6x^{10}y:x=\frac{2.5y}{x} -\frac{2.6x^{10}y}{x} =\frac{2.5y-2.6x^{10}y}{x} =\frac{y(2.5-2.6x^{10})}{x} =\\\\=\frac{10(2.5-2.6*(-1)^{10}}{-1} =\frac{10(2.5-2.6)}{-1} =\frac{10*(-0.1)}{-1} =1$

3)

$47.3t^{6}z^{2}:(t^{5}z)+2.7t^{9}z^{3}:(t^{8}z^{2})=47.3tz+2.7tz=50tz=50*(-3)*0.2=-30$

4)

$-9.4a^{25}b^{9}:a^{8}-0.6a^{10}*(a^{7}b^{9})=-9.4a^{17}b^{9}-0.6a^{17}b^{9}=10a^{17}b^{9}=\\\\=10*(1)^{17}*(-1)^{9}=-10$