Question

1) (5x-3)²-3(3+4x)=o
2) 2x²+x-5=0
3) X²-6x+13=0
решите уравнение

Answer 1

${(5x - 3)}^{2} - 3(3 + 4x) = 0 \ 25 {x}^{2} - 30x + 9 - 9 - 12x = 0 \ 25 {x}^{2} - 42x = 0 \D = {( - 42)}^{2} - 4 cdot 25 cdot 0 = 1764 \ sqrt{D} = sqrt{1764} = 42 \ x_1 = frac{42 + 42}{2 cdot25} = frac{84}{50} = 1.68 \ x_2 = frac{42 - 42}{2 cdot25} = frac{0}{50} = 0$