<em>y = 1200(.80)^t Plug in 5 for t (time).</em>
<em>y = 1200(.80)^5 </em>
<em>.80^5= 0.33</em>
<em>0.33 x 1200 = 395</em>
<em>Therefore, the value of the computer after 5 years has deteriorated to $396.</em>
Answer:
when x=20 so y=-12