Question

Aflați pe a
(a*2-40):8=12
[(a-1):100+90]:10-10=0
Va rog ajutați-mă

Answer 1

$(a \times 2 - 40) \div 8 = 12 \\ a \times 2 - 40 = 12 \times 8 = 96 \\ a \times 2 = 96 + 40 = 136 \\ a = 136 \div 2 = 68$

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Al doilea:

[(a-1):100+90]:10-10=0

[(a-1):100+90]:10=10

(a-1):100+90=10×10=100

(a-1):100=100-90=10

a-1=10×100=1000

a=1+1000

a=1001

Answer 2

Salutare!

(a×2-40):8=12

(a×2-40)=12×8

(a×2-40)=96

(a×2)=96+40

(a×2)=136

a=136:2

a=68

v: (68×2-40):8=

(136-40):8=

96:8=

12 ✔

[(a-1):100+90]:10-10=0

[(a-1):100+90]:10=10-0

(a-1):100+90]:10=10

(a-1):100+90]=10×10

(a-1):100+90]=100

(a-1):100=100-90

(a-1):100=10

(a-1)=100×10

(a-1)=1 000

a=1 000+1

a=1 001

v: [(1 001-1):100+90]:10-10=

(1 000:100+90):10-10=

(10+90):10-10=

100:10-10=

10-10=

0 ✔