Question

Решите уравнение x квадрате плюс 3 икс равно 4​

Answer 1

${x}^{2} + 3x = 4 \ {x}^{2} + 3x - 4 = 0 \ {x}^{2} + 4x - x - 4 = 0 \ x(x + 4) - (x + 4) = 0 \ (x + 4)(x - 1) = 0 \ x + 4 = 0 \ x - 1 = 0 \ x1 = - 4 \ x2 = 1$

Answer 2

${x}^{2} + 3x = 4 \ {x}^{2} + 3x - 4 = 0 \ d = {b}^{2} - 4ac = \ : = 9 + 16 = 25 \x_{1} = frac{ - 3 + sqrt{25}}{2} = \ = frac{ - 3 + 5}{2} = frac{2}{2} = 1 \ x_{2} = frac{ - 3 - 5}{2} = frac{ - 8}{2} = - 4 : .$