If the angles are complementary, their measures add up to 90 degrees. Given the measures of the two angles as \((x - 6)^\circ\) and \((3x + 3)^\circ\), we can set up the following equation:
\[ (x - 6) + (3x + 3) = 90 \]
Combining the terms, we get:
\[ x - 6 + 3x + 3 = 90 \ 4x - 3 = 90 \]
Thus, we can rewrite the equation as:
\[ 4x - 3 = 90 \]
Since this is the setup we derived from the relationship of complementary angles, the correct simplified equation for the angles is:
\[ 4x - 3 = 90° \]
So, the correct response from your options is:
4x°−3°=90° (left parenthesis 4 x minus 3 right parenthesis degrees equals 90 degrees)