Question

Să se afle solutia ecuației:7×{3×[5×(2x+3)-30]+2}-19=100

Answer 1

7×{3×[5×(2x+3)-30]+2}-19=100

7×{3×[5×(2x+3)-30]+2}=100+19

3×[5×(2x+3)-30]+2=119:7

3×[5×(2x+3)-30]=17-2

5×(2x+3)-30=15:3

5×(2x+3)=5+30

2x+3=35:5

2x=7-3

x=4:2

x=2

Succes!

Answer 2

Explicație pas cu pas:

7 · { 3 · [ 5 · ( 2x + 3 ) - 30 ] + 2 } - 19 = 100

7 · { 3 · [ 5 · ( 2x + 3 ) - 30 ]  + 2 } = 100 + 19

7 · { 3 · [ 5 · ( 2x + 3 ) - 30 ] + 2 } = 119

{ 3 · [ 5 · ( 2x + 3 ) - 30 ] + 2 } = 119 : 7

{ 3 · [ 5 · ( 2x + 3 ) - 30 ] + 2 } = 17

3 · [ 5 · ( 2x + 3 ) - 30 ] = 17 - 2

3 · [ 5 · ( 2x + 3 ) - 30 ] = 15

[ 5 · ( 2x + 3 ) - 30 ] = 15 : 3

5 · ( 2x + 3 ) - 30 = 5

5 · ( 2x + 3 ) = 5 + 30

5 · ( 2x + 3 ) = 35

2x + 3 = 35 : 5

2x + 3 = 7

2x = 7 - 3

2x = 4

x = 4 : 2

x = 2

119 : 7 = 17

7

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=49

 49

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