Answer
$-\dfrac{1}{20}$
Work Step by Step
Make the fractions similar using their LCD, which is $20$:
$\\=-\dfrac{1(5)}{4(5)}-\left(-\dfrac{1(4)}{5(4)}\right)
\\=-\dfrac{5}{20}-\left(-\dfrac{4}{20}\right)
\\=-\dfrac{5}{20}+\dfrac{4}{20}
\\=\dfrac{-5+4}{20}
\\=-\dfrac{1}{20}$
