Two angles are complementary if the sum of their measures is $90^\circ$.

If one of the angles is $57^\circ$, then the measure of the complementary angle $x$ can be found using the equation:

$x + 57^\circ = 90^\circ$

To solve for $x$:

$x = 90^\circ - 57^\circ$ $x = 33^\circ$

So, the measure of the angle $x$ is $33^\circ$.

Would you like any more details or have other questions?

Here are 5 related questions to consider:

1. What is the measure of an angle complementary to 45 degrees?
2. How do you determine if two angles are complementary?
3. What is the measure of an angle supplementary to a 57° angle?
4. Can angles be complementary if they are not adjacent?
5. How do complementary and supplementary angles differ?

Tip: Remember, complementary angles always add up to $90^\circ$, while supplementary angles add up to $180^\circ$.