Answer :
4n+10=18 4n-13=23 10n+8=78
4n+10-10=18-10 4n-13+13=23+13 10n+8-8=78-8
4n=8 4n=36 10n=70
n=2 n=9 n=7
4n+10-10=18-10 4n-13+13=23+13 10n+8-8=78-8
4n=8 4n=36 10n=70
n=2 n=9 n=7