Question

Find a negative real number such that the square of the sum of the number and 2 is equal to 400. (If there are two correct answers,either answer can be entered.)AnswerKeypadKeyboard Shortcuts

Answer 1

Answer: The number is - 22

Step-by-step explanation:

Let the negative real number be x.

The square of the sum of the number and 2 is (x + 2)^2.

given that the square of the sum of the number and 2 is equal to 400, it means that

(x + 2)^2 = 400

Taking the square root of both sides,

x + 2 = √400

x + 2 = ± 20

x + 2 = 20 or x + 2 = - 20

x = 20 - 2 or x = - 20 - 2

x = 18 or x = - 22

Since the number is negative, it is - 22