Question

Решите и распишите пж

Answer 1

Номер 9.

(1.2х-1,8у+3)(-2)-5(1,2х+1,8у-1,3)=

=-2,4х+3,6у-6-6х-9у+6,5=

=0,5-8,4х-5,4у

Номер 10.

4 2/5-(3-3/10)*3*1/81=

=4 2/5-2 7/10*3*1/81=

=4 2/5-8 1/10*1/81=

=4 2/5-1/10=

=4 4/10-1/10=

=4 3/10=

=4,3

0.7*30-1/2:2/67=

=21-1/2*67/2=

=21-16,75=

=4,25

4.3>4,25

Answer 2

9.

...........= -2,4х+3,6у-6-6х-9у+6,5= - 8,4х - 5,4у+0,5

10.

$4\frac{2}{5} -(3-\frac{3}{10} )*3*\frac{1}{81} =4,4-(3-0,3)*3*\frac{1}{81}=\\ \\ 4,4-2,7*\frac{1}{27}=4,4-\frac{27}{10}* \frac{1}{27}=4,4-0,1=4,3\\ \\ \\ \\ 0,7*30-\frac{1}{2}:\frac{2}{67} =21- \frac{1}{2}*\frac{67}{2}=21-\frac{67}{4}=\\ \\21-16\frac{3}{4} = 21-16.75=4.25\\ \\ \\ 4.3>4.25$