Question

Complete cada uma das igualdades de modo que se tornem verdadeiras:

A) (-10)*6+___=-20

B) 5*___+(-13)=27

C) (-3)*7+___=-30

D) 8*___+(-15)=-31

E) (-9)*4+___=10

F) 4*___-(-20)=-4

G) (-7)*5+____=15

H) -13+6*____=-25

Answer 1

a) (-10)*6+x=-20

-60+x=-20

x=-20+60

x=40

b) 5*x+(-13)=27

5x+(-13)=27

5x-13=27

5x=27+13

5x=40

x=40/5

x=8

c) (-3)*7+x=-30

-21+x=-30

x=-30+21

x=-9

d) 8*x+(-15)=-31

8x+(-15)=-31

8x-15=-31

8x=-31+15

8x=-16

x=-16/8

x=-2

e)(-9)*4+x=10

-36+x=10

x=10+36

x=46

f) 4*x-(-20)=-4

4x+20=-4

4x=-4-20

4x=-24

x=-24/4

x=-6

g) (-7)*5+x=15

-35+x=15

x=15+35

x=50

h) -13+6*x=-25

-13+6x=-25

6x=-25+13

6x=-12

x=-12/6

x=-2