Question

решите уравнение (5x+1)(5x-1)-(5x+1)^2=0

Answer 1

25x^2 - 1 - (25x^2 + 10x + 1) = 0
25x^2 - 1 - 25x^2 - 10x - 1 = 0 
- 10x - 2 =  0
- 10x = 2
10x = - 2
x = - 2/10
x = - 0,2