2х-5+(3х-12) -4х+16-(4х-15) 4х-18+(-9-5х) 18+х-(-14+6х)
2х-5+(3х-12)=2х-5+3х-12=5х-17 -4х+16-(4х-15)=-4х+16-4х+15=-8х+31 4х-18+(-9-5х)=4х-18-9-5х=-х-27 18+х-(-14+6х)=18х+х+14-6х=13х+14