Question

Find the root(s) of the equation x2 = 169? A) x = ±13 B) x = ± 13 C) x = 13 D) x = 13

Answer 1

I guess both A and B since they have the same exact answer: ±13

Explanation:

The square root of any positive number is both the positive (+) version of the root and the negative (-) version of the root.

169 is a perfect square and its positive square root is 13, but you must also include its negative square root, -13, so the roots of this equation are ±13.

That means both answer choices A and B are correct, since they are exactly the same.

Answer 2

We have this equation:

`x^2 = 169`

What we do is a square root on both sides, so we get:

`√(x^2)=√(169)`

`x = √(169)`

And now, we calculate the square root, remember tehre are always two results when the root index is even:

`\bold{x_1 = 13}`

`\bold{x_2 = -13}`

As 13 * 13 = (-13)*(-13)