Question

1) 15*(2х*11)=285
2) 7*(123-4х)=749

Answer 1

1)
15(2х+11) = 258
30х+165 = 258
30х = 258-165
30х = 93
х = 93 / 30
х = 3.1
2)
7(123-4х)=749
123-4х=7497
123-4х=107
4х=123-107
4х=16
х=164
х=4