Vreau explicație pas cu pas!​

Răspuns: b=10; a=29; x=1850

Explicație pas cu pas:

a)

1730÷[(21×b-33)-4]×20-16=184

1730÷[(21×b-33)-4]×20=184+16

1730÷[(21×b-33)-4]×20=200

1730÷[(21×b-33)-4]=200÷20

1730÷[(21×b-33)-4]=10

(21×b-33)-4=1730÷10

(21×b-33)-4=173

21×b-33=173+4

21×b-33=177

21×b=177+33

21×b=210

b=210÷21

b=10

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Verificare: 1730÷[(21×10-33)-4]×20-16=184

1730÷[(210-33)-4]×20-16=184

1730÷(177-4)×20-16=184

1730÷173×20-16=184

10×20-16=184

200-16=184

b)

[10+10×(a-10)]÷10-10=10

[10+10×(a-10)]÷10=10+10

[10+10×(a-10)]÷10=20

10+10×(a-10)=20×10

10+10×(a-10)=200

10×(a-10)=200-10

10×(a-10)=190

a-10=190÷10

a-10=19

a=19+10

a=29

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Verificare: [10+10×(29-10)]÷10-10=10

(10+10×19)÷10-10=10

(10+190)÷10-10=10

200÷10-10=10

20-10=10

c)

1200-(2x+100)÷19+2500=3500

1200-(2x+100)÷19=3500-2500

1200-(2x+100)÷19=1000

(2x+100)÷19=1200-1000

(2x+100)÷19=200

2x+100=200×19

2x+100=3800

2x=3800-100

2x=3700

x=3700÷2

x=1850

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Verificare:

1200-(2×1850+100)÷19+2500=3500

1200-(3700+100)÷19+2500=3500

1200-3800÷19+2500=3500

1200-200+2500=3500

1000+2500=3500

Răspuns:

Explicație pas cu pas:

a)

1 730 : [ ( 21 × b - 33 ) - 4 ] × 20 - 16 = 184

1 730 : [ ( 21 × b - 33 ) - 4 ] × 20 = 184 + 16

1 730 : [ ( 21 × b - 33 ) - 4 ] = 200 : 20

( 21 × b - 33 ) - 4 = 1 730 : 10

21 × b - 33  = 173 + 4

21 × b = 177 + 33

21 × b = 210

b = 210 : 21

b = 10

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b)

[ 10 + 10 × ( a - 10 ) ] : 10 - 10 = 10

[ 10 + 10 × ( a - 10 ) ] : 10 = 10 + 10

[ 10 + 10 × ( a - 10 ) ] : 10 = 20

10 + 10 × ( a - 10 ) = 20 × 10

10 × ( a - 10 ) = 200 - 10

a - 10 = 190 : 10

a - 10 = 19

a = 19 + 10

a = 29

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c)

1 200 - ( 2 x + 100 ) : 19 + 2500 = 3500

1 200 - ( 2 x + 100 ) : 19 = 3500 - 2500

( 2 x + 100 ) : 19 = 1 200 - 1 000

2 x + 100 = 200 × 19

2 x = 3 800 - 100

x = 3 700 : 2

x = 1 850