LearnAlgebraInequalities and absolute value

Absolute value equations

Absolute value is distance from zero, so it often gives two answers.

Lesson 3 of 3

Algebra: Inequalities and absolute value

measures how far is from 0. Distance is never negative. So has two answers, one on each side of zero.

Both 4 and are 4 steps from zero.
makes a V. Its point sits at the origin.

Work through it

Solve .

Split into two cases. or

Solve each. or

Solve .

Isolate first. Add 3.

Divide by 2.

Split and solve. or

Watch out for this

gives .

Distance can't be negative. This equation has no solution.

The short version
Isolate the absolute value. Then split: what's inside equals the number, or its negative.

Your turn