`-13 + (+18) = -13 +18 = 5`
`-20 + (+14) = -20 + 14 = -6`
`-25 + (+34) = -25 +34 = 34 -25 = 9`
`50 + (-14) = 50 -14 = 36`
`18+(-5) = 18-5 = 13`
\(3 ) ( − 13 ) + ( + 18 ) = 5\)
\(4 ) ( − 20 ) + ( + 14 ) = − 6\)
\(5) ( − 25 ) + ( + 34 ) = 9\)
\(6 ) ( + 50 ) + ( − 14 ) = 36\)
\(7 ) ( + 18 ) + ( − 5 ) = 13\)