If you use metric conversion (shown below), you will find that 9 meters = 90 cm. Tell me if you need further explanation.
It totally depends on the value of 'a', and if 'a' changes, then (6a-2) immediately changes too. Whatever 'a' is at the moment, (6a-2) is 2 less than 6 times 'a'.
Don't understand the question your asking
