Question

помогите пожалуйста!

Answer 1

$1)x(0.25x - 3) - (0.5x + 1)(0.5x - 1) = 0 \\ \\ {0.25x}^{2} - 3x - 0.25 {x}^{2} + 0.5x - 0.5x + 1 = 0 \\ \\ - 3x = 0 - 1 \\ \\ - 3x = - 1 \\ \\ x = - 1 \div ( - 3 )\\ \\ x = - \frac{1}{3}$


$2)(1.2 - x)(x + 1.2) + 1.8x + {x}^{2} = 0 \\ \\ 1.2x + 1.44 - {x}^{2} - 1.2x + 1.8x + {x}^{2} = 0 \\ \\ 1.8x = 0 - 1.44 \\ \\ 1.8x = - 1.44 \\ \\ x = - 1.44 \div 1.8 \\ \\ x = - 0.8$



$3)0.49 {x}^{2} - 3x - (0.7x + 2)(0.7x - 2) = 0 \\ \\ 0.49x^{2} - 3x - 0.49 {x}^{2} + 1.4x - 1.4x + 4 = 0 \\ \\ - 3x = 0 - 4 \\ \\ - 3x = - 4 \\ \\ x = - 3 \div ( - 4) \\ \\ x = 0.75$



$4)(1.6x + 1)(1 - 1.6x) - 64x(1 - 0.04x) = 0 \\ \\ 1.6x - 2.56 {x}^{2} + 1 - 1.6x - 64x + 2.56 {x}^{2} = 0 \\ \\ 64x = 0 - 1 \\ \\ 64x = - 1 \\ \\ x = - 1 \div 64 \\ \\ x = - \frac{1}{64}$


$1)(7x - 5 {)}^{2} + 67x - 49 {x}^{2} = - 2 \\ \\ 49 {x}^{2} - 25 + 67x - 49 {x}^{2} = - 2 \\ \\ 67x = - 2 + 25 \\ \\ 67x = 23 \\ \\ x = 23 \div 67 \\ \\ x = \frac{23}{67}$


$2)196x^{2} - (14x + 3 {)}^{2} + 80x = - 5 \\ \\ 196 {x}^{2} - 196x ^{2} + 9 + 80x = - 5 \\ \\ 80x = - 5 - 9\\ \\ 80x = - 14 \\ \\ x = - 14 \div 80 \\ \\ x = - 0.175$