a: \(19+\left(-15\right)+\left(-19\right)\)
\(=\left(19-19\right)+\left(-15\right)\)
=0-15
=-15
b: \(123-\left(59+213\right)+159\)
\(=123-59-213+159\)
\(=\left(123-213\right)+\left(159-59\right)\)
=100-90
=10
c: \(\left(-157+542\right)-\left(-257-58\right)\)
\(=-157+542+257+58\)
\(=\left(-157+257\right)+\left(542+58\right)\)
=600+100
=700
d: \(35-\left\{12-\left[\left(-14\right)+\left(-2\right)\right]\right\}\)
\(=35-\left\{12+14+2\right\}\)
=35-28
=7
e: \(-233+54-\left(-46\right)\)
\(=-233+54+46\)
=-233+(54+46)
=-233+100
=-133
f: \(\left(-624\right)-\left[\left(376+235\right)-35\right]\)
\(=-624-\left[376+200\right]\)
=-624-376-200
=-1000-200
=-1200
g: \(14\cdot\left(-25\right)+\left(-25\right)\cdot86\)
\(=\left(-25\right)\left(14+86\right)\)
\(=-25\cdot100=-2500\)
h: \(94\cdot\left(-15\right)+15\cdot\left(-6\right)\)
\(=15\cdot\left(-94\right)+15\left(-6\right)\)
\(=15\left(-94-6\right)=15\cdot\left(-100\right)=-1500\)
i: \(16\cdot23+\left(-23\right)\cdot6+\left(-300\right)\)
\(=23\left(16-6\right)-300\)
\(=23\cdot10-300=230-300=-70\)
k: \(7\cdot\left(-2\right)+29+2\cdot7\)
\(=29+\left(7\cdot2-7\cdot2\right)\)
=29
l: \(2^3\cdot35+15\cdot8-50\cdot8\)
\(=8\cdot35+8\cdot15-8\cdot50\)
\(=8\left(35+15-50\right)=8\cdot0=0\)
m: \(42\cdot\left(-11\right)+42\left(-101\right)+42\cdot12\)
\(=42\left(-11-101+12\right)\)
\(=42\cdot\left(-100\right)=-4200\)
