3 years ago

Please explain as well 3x+5y=21 4x-2y=-244x−2y=−24

Mathematics

1 answer:

hodyreva [135]3 years ago

3 0

Step-by-step explanation:

3x + 5y = 21 * (-4) •••••• -12x -20y = -84 (a)

4x - 2y = -24 * (3) •••••• 12x -6y = -72 (b)

(a) + (b)

-26y = -156

y = 6

3x + 5 * 6 = 21

3x = 21 - 30

3x = -9

x = -3

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