To solve for \( x \), we're likely looking at the relationship between the angles given, 51° and \( (3x)° \). The problem seems to imply some kind of equation involving these angles.
For example, if these angles are to be supplementary (adding up to 180°), then:
\[ 51° + 3x = 180° \]
Subtracting 51° from both sides:
\[ 3x = 180° - 51° \] \[ 3x = 129° \]
Now, divide both sides by 3:
\[ x = \frac{129°}{3} \] \[ x = 43° \]
If that answer is rejected as incorrect, we should consider the possibility that they are complementary (adding up to 90°):
\[ 51° + 3x = 90° \]
Again, we can subtract 51° from both sides:
\[ 3x = 90° - 51° \] \[ 3x = 39° \]
Now divide by 3:
\[ x = \frac{39°}{3} \] \[ x = 13° \]
So, if the angles are complementary, \( x = 13° \). Please check to see which relationship is correct based on your context to ensure the right interpretation.