3х+2(5х+7)=40 3(8х-9)-15х=0

Question

3х+2(5х+7)=40 3(8х-9)-15х=0

Answer 1

3х+10х+14=40
13х=40-14
13х=26
х=26:13
х=2

24х-27-15х=0
24х-15х=27
9х=27
х=27:9
х=3