(1)2x－3y＝5 x＋2y＝1 (2)u－9.8t－1＝0 u／3－1＝3t (3)x－5y＝16 5y－5x＝4 (4)2x－3y＝5 x＋y＝5／3 （5）21x＋23y＝243 23x＋21y＝241 Find x, Y. quick, I'll make it clear. (1)2x－3y＝5 x＋2y＝1 (2)u－9.8t－1＝0 u／3－1＝3t (3)x－5y＝16 5y－5x＝4 (4)2x－3y＝5 x＋y＝5／3 （5）21x＋23y＝243 23x＋21y＝241

(1) 2x-3y = 5.1x + 2Y = 1.2 from formula 2 we get x = 1-2y.3 by substituting formula 3 into Formula 1 we get 2 (1-2y) - 3Y = 52-4y-3y = 5-7y = 3Y = - 3 / 7X = 1-2y = 1-2 * (- 3 / 7) = 1 + 6 / 7 = 13 / 7, so x = 13 / 7, y = - 3 / 7 (2) u-9.8t-1 = 0.1U / 3-1 = 3t.2 from Formula 1 we get u = 9.8t + 1.3 from Formula 1 we get U-3 = 9t.4 from formula 2

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