The slope \(a = \dfrac{ T ( 98.6 ) – T ( 32 ) }{98.6 – 32} = \dfrac{37}{66.6} = \dfrac{370}{666} = \frac{5}{9}\). Thus, \(T ( x ) = \frac{5}{9}x + b\), for some constant value of \(b\). To find the value of \(b\), use the fact that \(T ( 32 ) = 0\) to get \(T ( 32 ) = \frac{5}{9}( 32 ) + b = 0\). Thus, \(b = - \dfrac{160}{9}\). Therefore, \(T ( x ) = ( 5x – 160 ) \div 9\)