[tex]\begin{gathered} \text{For P1} \\ (30;150,000) \\ For\text{ P2} \\ (50;120,000) \\ \text{Slope}-\text{intercept form} \\ y=mx+b \\ To\text{ find m} \\ m=\frac{y2-y1}{x2-x1} \\ m=\frac{120,000-150,000}{50-30}=\frac{-30,000}{20}=-1,500 \\ y=-1,500x+b \\ To\text{ find b using P1 (30;150,000)} \\ 150,000=-1,500(30)+b \\ 150,000=-45,000+b \\ b=150,000+45,000 \\ b=195,000 \\ \text{Hence} \\ \text{The linear equation is y=-1,500x+195,000} \\ \\ \text{Part b} \\ Number\text{ sold is 60} \\ y=-1,500(60)+195,000 \\ y=-90,0000+195,000 \\ y=105,000 \\ To\text{ sell 60 }condominiums\text{ the price should be \$105,000} \end{gathered}[/tex]
