Since the angles \( \angle MAT \) and \( \angle TAH \) are supplementary, their measures add up to 180 degrees. Therefore, we can set up the equation as follows:
\[ \angle MAT + \angle TAH = 180^\circ \]
Substituting the expressions for \( \angle MAT \) and \( \angle TAH \):
\[ (6x - 6) + (4x - 14) = 180 \]
Now, combine like terms:
\[ 6x + 4x - 6 - 14 = 180 \]
This simplifies to:
\[ 10x - 20 = 180 \]
So the equation to solve for \( x \) is:
\[ 10x - 20 = 180 \]