Question

Решите уравнение 81x^2-(4-9x)^2=56

Answer 1

81x^2 - ( 4 - 9x ) ^2 = 56 ; 81x^2 - ( 16 - 72x + 81x^2 ) = 56 ; 81x^2 - 16 + 72x - 81x^2 = 56 ; 72x = 56 + 16 ; 72x = 72 ; X = 1