Решите уравнения. ----------------------------------------------------------------- 1) (х-5)*(2х-4)=0; 2) -(5+2х)-3х=4;
1) (x-5)*(2x-4) = 0 2x²-4x-10x+20 = 0 2x²-14x+20 = 0 I : 2 x²-7x+10 = 0 D=√49-40=√9=3. 7+3 10 x₁ = ____ = ____ = 5. 2 2 7-3 4 x₂ = ____ = ___ = 2. 2 2 Ответ : 2 ; 5. 2) -(5+2x)-3x = 4 -5-2x-3x = 4 -2x-3x = 4+5 -5x = 9 x = - 1,8 Ответ : - 1,8.