
Jim B. answered 03/09/15
Tutor
4.8
(111)
Experienced teacher and author tutoring in Math and Computer Topics
Jokes about him making free throws aside, let t be the number of two point shots he made, and f be the number of free throws.
t + f = 25 total shots made, and we know he must have made at least one free throw because if he made 25 two-point shots he would have had 40 points.
2t + f = 40 is the point value of all of his made shots.
You can use graphing methods, substitution, or linear combinations (elimination) to solve this system.
If we multiply the top equation by -1:
-t - f = -25
then add the bottom equation
-t - f = -25
2t + f = 40
-------------
t = 15, so he made 15 two point shots, for a subtotal of 30 points
15 + f = 25, so he made 10 free throws, for a subtotal of 10 points
Now make sure this is consistent with the problem of 25 shots and 40 points