79.7k views
4 votes
Solve for x |x| = 4 ​

User Elmart
by
8.4k points

1 Answer

2 votes

Answer:

x = 2

Explanation:

You want the value of x that satisfies x|x| = 4.

Domain

The absolute value function splits the domain of the equation into two parts.

For x < 0, the equation is ...

x(-x) = 4

x² = -4

There are no real solutions in this domain.

For x ≥ 0, the equation is ...

x² = 4

x = √4 = 2

The only solution is x = 2.

__

Additional comment

In the attachment, we have rewritten the equation to ...

x|x| -4 = 0

The graphing calculator readily identifies x-intercepts, so this is a convenient way to find the solution. You will notice that for x < 0, the graph is of -x²-4, which is never zero.

<95141404393>

Solve for x |x| = 4 ​-example-1
User Tlaminator
by
8.3k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories