ensure all fractions have the same denominator
we require - [tex]\frac{1}{4}[/tex] = - [tex]\frac{4}{16}[/tex]
thus - [tex]\frac{7}{16}[/tex] - [tex]\frac{4}{16}[/tex] - [tex]\frac{5}{16}[/tex]
take out a common factor [tex]\frac{1}{16}[/tex]
= [tex]\frac{1}{16}[/tex] (- 7 - 4 - 5 )
= [tex]\frac{1}{16}[/tex] × - 16 = - 1
