John morse corporation buys a van for $16,000. the estimated life of the van is four years. the residual value of the van is $4,000. after two years, the van is sold for $8,000. what was the difference between the book value and the amount received from selling the van if john used the straight-line method of depreciation?

A.  x+y = 50; y=  x+20

B.Ted spend on practicing the breaststroke every day

C. Not possible as he spent 50 minutes in total for both styles.

Step-by-step explanation:

Let x = Number of minutes spent on butterfly stroke.

y= Number of minutes spent on breaststroke.

Part A.

Total time : x+y = 50   ...(i)

"He practices the breaststroke 20 minutes more than he practices the butterfly stroke."

y=  x+20 ....(ii)

Required pair of linear equations: x+y = 50; y=  x+20

Part B. Put value of y from (ii) in (i) ,

From (ii), y= 15+20= 35

Ted spend 35 minutes on practicing the breaststroke every day.

Part C. If x= 45

Then, y= 45+20= 65 > 50 which is not possible as he spent 50 minutes in total for both styles.