Question

solve for n algebraically. (2n+1) chose 2 = n+50

Answer 1

(2n+1)choose 2 = (2n+1)!/((2n-1)2!)=n(2n+1)
Equate to n+50
n(2n+1)=n+50
2n^2-50=0
n^2-25=0
n=+/-5
Since (2(-5)+1) choose 2=0 will invalidate the inequality, -5 is rejected.
=>
n=5