Relax

Respuesta :

x + 1/4x = 15
4/4x + 1/4x = 15
5/4x = 15
5x = 60
x = 12
maj9

x+(1/4)*x = 15 // - 15

x+(1/4)*x-15 = 0

5/4*x-15 = 0 // + 15

5/4*x = 15 // : 5/4

x = 15/5/4

x = 12