Algebra word problem

Question

John was paid $10 for each door that he painted that did not need repainting by the painter. For each door that needed to be redone, he was fined $5. On a bad day, he painted 25 doors, but made a total of only $10. How many doors did he paint that did not need to be repainted?

Answer 1

d represents the good doors

25 - d represents the redo doors

 

10d - 5(25 - d) = 10

 

Can you solve for d and answer?