Step 1
Let the numbers be x and y and let us assume x is the bigger number
The equations then are;
[tex]\begin{gathered} x+y=16----(1) \\ x-y=20--(2) \end{gathered}[/tex]Step 2
Add equations 1 and 2
Hence,
[tex]\begin{gathered} 2x=36 \\ \frac{2x}{2}=\frac{36}{2} \\ x=18 \end{gathered}[/tex]Step 3
Find the value of y from equation 2
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