Question

a+b=-7
a-b=3
Determinați numerele

Answer 1

$\left\{\begin{matrix}</p><p>a + b = - 7\\ </p><p></p><p>a - b = 3\end{matrix}\right.$

$a + a + b - b = - 7 + 3$

$2a = - 4 \: | \div 2$

$a = - 2$

$a + b = - 7$

$- 2 + b = - 7$

$b = - 7 + 2$

$b = - 5$