Simultaneous equations - Find the values of y and x: 3

3x + 5y = 19 and4x - 2y = -18Find the common multiple for 3x and 4x to enable it to be cancelled out. In this case it would be 124(3x + 5y) = 4(19) 3(4x - 2y) = 3(-18) 12x + 20y = 76 12x - 6y = -54 12x + 20y = 76- 12x - 6y = -54 12x - 12x = 0; 20y - (-6y) = 26y; 76 - (-54) = 130Therefore, 26y = 130y = 130/26y = 5Therefore,3x + 5y = 193x + 5(5) = 193x +25 = 193x = 19 - 253x = -6x = -6/3x = -2Therefore, y = 5 and x = -2

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Answered by Zyen U. Maths tutor

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