a) 25 + ( - 13 + 8 )
= 25 - 13 + 8
= 20
b) 7 + ( - 12 + 43 ) - [ 2 + ( 19 - 34 ) ]
= 7 - 12 + 43 - [ 2+ 19 - 34 ]
= - 5 + 43 - 2 - 19 + 34
= 61
\(25+\left(-13+8\right)\)
\(=25-13+8\)
\(=12+8\)
\(=20\)
\(7+\left(-12+43\right)-\left[2+\left(19-34\right)\right]\)
\(=7-12+43-\left[2+19-34\right]\)
\(=7-12+43-2-19+34\)
\(51\)
A) 25 + (-13 +8)
= 25 + (-13)+8
= 12 +8
= 20.
b) 7 + ( - 12 + 43) - [ 2 + ( 19 - 34 ) ]
= 7 + (- 12) + 43 - 2 - 19 + 34
= (-5) + 43 - 2 - 19 + 34
= 38 - 2 - 19 + 34
= 36 - 19 + 34
= 17 + 34
= 51.