Complementary angles are two angles whose sum equals 90°.

Given the two angles $(x + 7)^\circ$ and $(3x)^\circ$, we can set up the following equation to represent their relationship:

$(x + 7) + (3x) = 90$

This equation can be used to determine the value of $x$.

Would you like me to solve this equation for you or provide more details on any steps?

Here are 5 related questions:

1. How do you solve linear equations like this one?
2. What are supplementary angles, and how are they different from complementary angles?
3. What if the sum of two angles equals 180° instead of 90°?
4. How can this method be applied to solving problems with more than two angles?
5. How can you verify if two angles are truly complementary?

Tip: Always check if your final angle measures add up to the specified sum (like 90° for complementary or 180° for supplementary).