Question

5 times a number is 14 less than the square of that number. Find the positive solution.

Answer 1

Write the word problem in algebraic form:

n2 -14 = 5n

Write as a quadratic:

n2 - 5n - 14 = 0

Factor:

(n+2)(n-7) = 0

Solve:

n+2 = 0    =>   n = -2

n-7 = 0    =>   n = 7

positive solution is 7.   (14 less than 72 = 35 which is also 5 times 7)

Answer 2

Answer:

The positive solution is 7.

Step-by-step explanation:

Let the number be x, then we have:

5x = x^2 - 14

x^2 - 5x - 14 = 0

(x - 7)(x + 2) = 0

x =7, -2.