Question

The sum, S, of the first n even integers can be found using the equation S=n(n+1). If the sum of the first n even integers is 240, then what is n?​

Answer 1

S=n(n+1) therefore 240=n(n+1), 240=2n +n therefore i have to move all to one place and equate to Zero so that will become quadratic equation 240-2n -n=0 so -n -2n +240=0