Question

Given the function f(x) = –5|x + 1| + 3, for what values of x is f(x) = –12?

Answer 1

The correct answer is x = 2 and x = -4.

In order to solve for this, you first need to plug in the f(x) value and solve for the absolute value statement.

f(x) = -5|x + 1| + 3

-12 = -5|x + 1| + 3 ---> subtract 3 from both sides.

-15 = -5|x + 1|----> divide both sides by -5.

3 = |x + 1|

Now that we have solved for the absolute value portion, we need to solve this equation twice. Once removing the absolute value and solving and the other by removing it and making the 3 negative. This is because even if the inside of the markers was -3, it would give us a 3 answer.

3 = x + 1

2 = x

Then the negative version.

-3 = x + 1

-4 = x

And there are your two answers.