Question

If the square of a positive integer is added to 2 times the integer the result is 48. find the integer.

Answer 1

6

Explanation:

let n be the positive integer, hence

n² + 2n = 48 ( subtract 48 from both sides )

n² + 2n - 48 = 0 ← in standard form

(n + 8)(n - 6) = 0 ← in factored form

equate each factor to zero and solve for n

n + 8 = 0 ⇒ n = - 8

n - 6 = 0 ⇒ n = 6

Since n is a positive integer then n = 6