Question

What two values can d have if d2 (squared) = 9?

Answer 1

Answer:

d = 3  &  d = -3

Step-by-step explanation:

the equation to solve is  $d^2=9$

Let's remember some properties of numbers and radicals.

Let's take the number 2 for example.

We know  

$2^2=4$

Also

$(-2)^2=4$ as well

Since negative TIMES negative also gives us positive.

How do we get the reverse answer? Simple. We square root it. So we would have:

$\sqrt{4}=2$

and

-2, since we now know this.

Let's do this process and take square root of our equation to get:

$d^2=9\\d=\sqrt{9} \\d=3$

and also d = -3

Hence, two values of d are  d = 3  &  d = -3