Question

Calcule o valor das expressoes 12-(-3)+(-1)-(-7)

Answer 1

$\large\boxed{\begin{array}{l} \displaystyle \sf 12-(-3)+(-1)-(-7)\\\\\displaystyle \sf 12+3-1-(-7)\\\\\displaystyle \sf15-1-(-7)\\\\\displaystyle \sf 14-(-7)\\\\\displaystyle \sf 14 +7\\\\\displaystyle \sf 21 \sf\end{array}}$