1) (-2,6 + 4,5) + (2,8 + (-0,9)) 2) (-5 3/7 + 5 1/14) + (5/7 + (-5/14))
ПАМАГИТЕ УМАЛЯЮ

1) (-2,6+4,5)+(2,8+(-0,9))=4,5-2,6+2,8-0,9=1,9-0,9=1

2) (-5 3/7+5 1/14)+( 5/7 +(-5/14))=(-38/7+71/14)+(5/7-5/14)=71/14-38/7+5/7-5/14=71/14-76/14+10/14-5/14=-5/14+10/14-5/14=10/14=5/7