You divide 690 by 100 which is 6.9
Therefore, one 50cent coin is 6.9g
You would distibute first distribute
6x-10=8
add 10 on both sides
6x=18
Then you divide 6 on both sides to get x by itself so
x=3
No, because 3/2 is actually 1 1/2. 2/3 isn't even 1
