3. Решите уравнение: a) 13²-x²= 0 б) 9у²-36=0 в) (3-x)²-x(x+1,5)=9

a) \(13^2 - x^2 = 0\) => \(169 - x^2 = 0\) => \((13 - x)(13 + x) = 0\) => \(x = 13\) или \(x = -13\) б) \(9y^2 - 36 = 0\) => \(9y^2 = 36\) => \(y^2 = 4\) => \(y = 2\) или \(y = -2\) в) \((3 - x)^2 - x(x + 1.5) = 9\) => \(9 - 6x + x^2 - x^2 - 1.5x = 9\) => \(-7.5x = 0\) => \(x = 0\)