Question

Ma ajutati la ex 6 si 7 va rog dau 20 de puncte

Answer 1

Răspuns:

6.

a) 14×2+14×21-14×3=

=14×(2+21+3)

=14×26

=364

b) 516×18+516×89-516-516×6

=516×(18+89+1+6)

=516×114

=58.824

d) 5 ²⁰+5²¹+5²²=

=5²⁰+²¹+²²

=5⁶³

7.

a) x+31=125

x=125-31

x=94

b) 2x-7=11

2x=11+7

2x=18

x=18:2

x=9

c) 78-x=45

x=78-45

x=33

d) 61+5x=456

5x=456-61

5x=395

e) 2×(x-7)=44

(x-7)=44:2

(x-7)=22

x=22+7

x=29

f) x:8=11

x=11×8

x=88

g) (2x+10)÷4=21

(2x+10)=21×4

(2x+10)= 84

2x=84-10

2x=74

x=74:2

x=37