C
A
B

\(A=\left\{-2;-1;0;1\right\}\)

A

A

=228390

7009mm\(^2\)

\(58=2\cdot29\)

a) \(A=\dfrac{-5}{9}+\dfrac{3}{5}+\dfrac{-3}{9}+\dfrac{-2}{5}\)
\(A=\left(\dfrac{-5}{9}+\dfrac{-3}{9}\right)+\left(\dfrac{3}{5}+\dfrac{-2}{5}\right)\)
\(A=\dfrac{-8}{9}+\dfrac{1}{5}\)
\(A=\dfrac{-3119}{4005}\)

B

4)
\(11+\left(15-x\right)=1\)
\(15-x=1-11\)
\(15-x=-10\)
\(x=15-\left(-10\right)\)
\(x=25\)

5) 
\(4-\left(27-3\right)=x-\left(13-4\right)\)
\(4-24=x-9\)
\(x-9=-20\)
\(x=-20+9\)
\(x=-11\)
 

\(x=3\)