Answer :
[tex]A+B=76\\
A-B=38\ \ --->\ \ A=38+B\\\\
38+B+B=76\\
38+2B=76\ \ | subtract\ 38\\2B=38\ \ \ | divide\ by\ 2\\
B=19\\A=57\\\\
\frac{A}{B}=\frac{57}{19}=3[/tex]
A+B=76
A-B=38
A=38+B
Substitute into other
38+B+B=76
2b=38
b=19
A+19=76
A=38
B=19
A-B=38
A=38+B
Substitute into other
38+B+B=76
2b=38
b=19
A+19=76
A=38
B=19