Помогите плез Даю 20 балов
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16) 3 x^2 + x^2 + 5x + 2x - 2 = 0; 4x^2 + 7x - 2 = 0; D = b^2 - 4 a c = 7^2 - 4 * 4*(-2) = 49 + 32 = 81= 9^2; x1 = (- 7 - 9)/ 2*4 = -16 / 8 = -2; x2 = ( - 7 + 9) /2*4 = 2 / 2*4 = 1/4 = 0,25 17) 5x + x = 12* 5; 6x = 60 ; x = 60 : 6 ; x = 10