8.3x+2x-60.05=300 как решить ето (1.65-0.3x): 0.34=4.5 и ето

1) 8.3х+2х-60.05=300
8.3х+2х=300+60.05
8.3х+2х=360.05
10.3х=360.05
х=360.05÷10.3
х=34.96

2) (1.65-0.3х)÷0.34=4.5
1.65-0.3х=4.5×0.34
1.65-0.3х=1.53
0.3х=1.65-1.53
0.3х=0.12
х=0.12÷0.3
х=0.4