\(\frac{2 x}{3}+\frac{31}{2}+9=0\)
We arrange the equation in the form
\(\frac{x}{t}+\frac{1}{b}=1\)
where \(u\) and \(b\) are the intercepts on the \(x\) and \(u\) - avis
thus:
\(\frac{21}{3}+\frac{31}{2}-9=0\)
dividing through by \(-9\). we have.
\(\frac{x}{\frac{3}{2} x-9}+\frac{y}{\frac{2}{3} x-9}=\frac{-9}{-9}\)
Now we compare with
\begin{aligned}
\frac{x}{a}+\frac{y}{b} &=\left(a=\frac{-27}{2}, b=-6\right) \\
a+b &=\frac{-27}{2}+(-6) \\
&=\frac{-27}{2}-6 \\
&=\frac{-39}{2}=-19.5
\end{aligned}