Answer:
Tony make 4 half-court shots and misses 16 half-court shots.
Step-by-step explanation:
Given:
Points earned for every successful, half-court shots = 
Points deducted for missing the shots =
or 
Total number of shots in the game = 
Final points earned by Tony = 
According to the question:
Let the number of successful half-court shot be
And the number of shots missed be 
So,
In terms of points we can re-write it as:
⇒ 
⇒ 
⇒ 
⇒ 
⇒
⇒ 
⇒ 
⇒ 
Tony make 'x' shots that is 4 and the number of shot he missed is (20-x) =(20-4)=16