SOLUTION: The average​ profit/loss of a company​ (in thousands of​ dollars) was documented for 30 months. The 4th month showed a loss of ​$3000​, however the 20th month showed a pr

Algebra ->  Linear-equations -> SOLUTION: The average​ profit/loss of a company​ (in thousands of​ dollars) was documented for 30 months. The 4th month showed a loss of ​$3000​, however the 20th month showed a pr      Log On


   

Question 1148228: The average​ profit/loss of a company​ (in thousands of​ dollars) was documented for 30 months. The 4th month showed a loss of ​$3000​, however the 20th month showed a profit of ​$5000. Assuming the​ profit/loss is​ linear, write the equation of the​ line, in​ slope-intercept form, that represents the​ profit/loss for each month x. Use this result to predict the​ profit/loss after 60 months.
​Hint: Use the ordered pairs (4,-3) (20,5).
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Use the general point-slope formula
+%28+P+-+%28-3%29+%29+%2F+%28+x+-+4+%29+=+%28+5+-%28-3%29+%29+%2F+%28+20+-+4+%29+
+%28+P+-+%28-3%29+%29+%2F+%28+x+-+4+%29+=+8+%2F+16+
+%28+P+-+%28-3%29+%29+%2F+%28+x+-+4+%29+=+1%2F2+
+P+%2B+3+=+%281%2F2%29%2A%28+x+-+4+%29+
+P+=+%281%2F2%29%2Ax+-+2+-+3+
+P+=+%281%2F2%29%2Ax+-+5+
After 60 months, the ordered pair is ( 60, P )
+P+=+%281%2F2%29%2A60+-+5+
+P+=+30+-+5+
+P+=+25+
25 thousand is the profit after 60 months
Here's the plot:
+graph%28+400%2C+400%2C+-50%2C+50%2C+-10%2C+10%2C+%281%2F2%29%2Ax+-+5+%29+