We are given the expression:
[tex]a-b=0[/tex]
To simplify
Let us add b to both sides
[tex]a-b+b=0+b[/tex]
Simplifying further
[tex]a=b[/tex]
Then, we are told to find the value of ab
[tex]\begin{gathered} ab=a\times b \\ \sin ce\text{ } \\ b=a \\ \text{then} \\ a\times b=a\times a=a^2 \\ ab=a^2 \end{gathered}[/tex]
Thus the answer is
a² (option A)
