Question

3x+4y=-17 and 5x+7y=-19 by elimination​

Answer 1

Step-by-step explanation:

$\huge\bold{\gray{\sf{Answer:}}}$

Explanation:

3x+4y=-17.......(I)

5x+7y=-19.......(ii)

Multiply equation 1 and 2 by 5 and 3 respectively

3x+4y=-17.......(I) ×5

5x+7y=-19.......(ii) ×3

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15x+20y=-85

15x+21y= -58

(-). (-)=(+)

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-y=-28

$\bold{\red{\boxed{y=28}}}$

Put the value of y in equation 1

$3x + 4y = - 17$

$= > 3x + 4 \times 28 = - 17$

$= > 3x + 112 = - 17$

$= > 3x = - 17 - 112$

$= > 3x = - 129$

$= > x = - \frac{129}{3} = - 43$

$\bold{\boxed{\green{x = - 43}}}$