Gleichungssysteme Gleichsetzen: 1) 3+2a=b; 3b -2a=-2

Question

1)3+2a=b

3b -2a=-2

2) 2y=4x-4

12x+4y=22

Comments

Kein "hallo", keine Frage? :P

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Vergessen :D sorry

Answer 1

3+2a=b
3b -2a=-2

2a - b = -3
-2a + 3b = -2  | addieren
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-b + 3b = -3 -2
2b = -5
b = -2.5

3 + 2 * a = -2.5
2 * a = -2.5 - 3 = -5.5
a = -2.75

Probe
3b - 2a = -2
3 * (-2.5 )  -2 * ( -2.75 ) = -2
-7.5 + 5.5  = -2  | stimmt

Answer 2

1)

3 + 2a = b --> 2a = b - 3
3b - 2a = -2 --> 2a = 3b + 2

Gleichsetzen 2a = 2a

b - 3 = 3b + 2
2b = -5
b = -2.5

2a = b - 3 = -2.5 - 3 = -5.5
a = -2.75

Comments

2)

2y = 4x - 4
12x + 4y = 22 --> 4y = 22 - 12x --> 2y = 11 - 6x

Gleichsetzen 2y = 2y

4x - 4 = 11 - 6x
10x = 15
x = 1.5

2y = 4*1.5 - 4 = 2
y = 1