Question

2. Determină valoarea lui "a" din egalitățile:
a) [1 +2 x ( 6+6:a)-5]: 6=2
b) 180 : 2 + [(50 xa: 10 +90) + 10 - 25 x 4] = 100
c) (36: a +63:9): 2 = 8​

Answer 1

Răspuns:

[1 +2 x ( 6+6:a)-5]: 6=2

[1+2x(6+6:a)-5]=2x6

1+2x(6+6:a)-5=12

1+2x(6+6:a)=12+5

1+2x(6+6:a)=17

2x(6+6:a)=17-1

2x(6+6:a)=16

(6+6:a)=16:2

6+6:a=8

6:a=8-6

6:a=2

a=6:2

a=3

180 : 2 + [(50 xa: 10 +90) + 10 - 25 x 4] = 100

90+[(50xa:10+90)+10-100]=100

[(50xa:10+90)+10-100]=100-90

(50xa:10+90)+10-100=10

(50xa:10+90)+10=10+100

(50xa:10+90)+10=110

(50xa:10+90)=110-10

50xa:10+90=100

50xa:10=100-90

50xa:10=10

50xa=10x10

50xa=100

a=100:50

a=2

(36: a +63:9): 2 = 8

(36:a+7):2=8

(36:a+7)=8x2

36:a+7=16

36:a=16-7

36:a=9

a=36:9

a=4