X+(x+31)=121. помогите

Question

X+(x+31)=121. помогите

Answer 1

Х+(х+31)=121
х+х+31=121
2х+31=121
2х=121-31
2х=90
х=45

Answer 2

Х +( Х + 31 ) = 121
Х + Х + 31 = 121
2Х = 121 - 31
2Х =  90
Х = 90 : 2
Х = 45