Question

4x(3-x)= 25- (2x-1)^2

Answer 1

$12x - 4 {x}^{2} = 25 - ( {4x}^{2} - 4x + 1) \\ 12x - 4 {x}^{2} = 25 - {4x}^{2} + 4x - 1 \\ 12x - {4x}^{2} = 24 - 4 {x}^{2} + 4x$

$12x - 4 {x}^{2} - 24 + 4 {x}^{2} - 4x = 0 \\ 8x - 24 = 0 \\ 8x = 0 + 24 = 24 \\ x = 24 \div 8 = 3$

Ответ:х=3