Question

Calculează:a)-(-54+21)+(-19+21)-(54+17)+2
b)-(-7+15-67)+(-67-7+15)+10
c)[-9+13-(-9+13-10)]-(-7+17)
d) (-11+37-42)+(-37+45+11)-5​

Answer 1

a) -(-54+21)+(-19+21)-(54+17)+2=

=-(-33) +2-71+2

=37-21

=-34

b) - (-7+15-67)+(-67-7+15)+10=

=-(-59)+(-469+15)+10

=59+(-454)+10

=-385

c) [-9+13-(-9+13-10)]-(-7+17)=

=(-9+13-(-6)) -10

=10-10

=0

d) (-11+37-42)+(-37+45+11)-5=

=(-16)+19-5

=-2