Tolong yaa pakai cara nomor 34

2x+15=4x-45
-2x=-60
x=30

5z+10=2x+15
5z+10=75
5z=65
z=15

3y+6+5z+10=180
3y+16+65=180
3y=99
y=33

x+y+z= 30+33+15 = 99