What is a positive number that equals 30 when added to it squared

Answer: 5

Step-by-step explanation:

Let x represent the number, then

x² + x = 30

x² + x - 30 = 0

(x + 6) (x - 5) = 0

x + 6 = 0 x - 5 = 0

x = - 6 x = 5

↓

not valid since the restriction is that x > 0 (a positive number)

So, x = 5