Complementary angles are two angles whose measures add up to \(90^\circ\).
Given the measures of the two angles are \( (x + 3) \) and \( (4x - 2) \), we can set up the equation as follows:
\[ (x + 3) + (4x - 2) = 90 \]
Now we need to fill in the blanks as per your request.
The equation becomes:
\[ (x + 3) + (4x - 2) = 90 \]
So to fill in the blanks:
\[ ( x + 3 ) + ( 4x - 2 ) = 90 \]
This is the equation representing the sum of the measures of the two complementary angles.