how to resolve this ecuation

-2 1/4  =  r - 4/5     add 4/5 to both sides

-2 1/4 + 4/5  = r         2 1/4 = 9/4

- 9/4 + 4/5 = r          get common denominator of 20

-45/20 + 16/20 = r     simplify

-29/20 = r

- 1 9/20 = r

-2 1/4=r-4/5

\(-2\frac{1}{4}=r-\frac{4}{5} \)

\(r=\frac{4}{5}-\frac{9}{4}=\frac{4\times 4-9\times 5}{5\times 4} =-\frac{29}{20} \)

\(r=-1\frac{9}{20}= -1.45\)

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