The phrase a number means an arbitrary variable. We can pick any letter a-z except for i and e.
Let's choose x.
Twice a number means we multiply x by 2:
2x
The sum of twice a number and 6:
2x + 6
Ten times the sum of twice a number and six
10(2x + 6)
Let's choose x.
Twice a number means we multiply x by 2:
2x
The sum of twice a number and 6:
2x + 6
Ten times the sum of twice a number and six
10(2x + 6)