Problem:
Which of the following is equal to 9−62+9+62?
Answer Choices:
A. 32
B. 26
C. 272
D. 33
E. 6
Solution:
Let k=9−62+9+62. Squaring both sides and simplifying results in
k2=9−62+2(9−62)(9+62)+9+62=18+281−72=18+29=24
Because k>0,k=(B)26.
The problems on this page are the property of the MAA's American Mathematics Competitions