Question

y+30%=-1,3

y-25%y=1/2

Answer 1

\(a)\) \(y+30\%=\dfrac{-1}{3}\)

\(\Rightarrow y+\dfrac{3}{10}=\dfrac{-1}{3}\)

\(\Rightarrow y=\dfrac{-19}{30}\)

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\(b)\) \(y-25\%y=\dfrac{1}{2}\)

\(\Rightarrow1y-\dfrac{1}{4}y=\dfrac{1}{2}\)

\(\Rightarrow y\left(1-\dfrac{1}{4}\right)=\dfrac{1}{2}\)

\(\Rightarrow y\dfrac{3}{4}=\dfrac{1}{2}\)

\(\Rightarrow y=\dfrac{2}{3}\)

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Answer 2

a, \(y+30\%=-1,3\)

\(\Rightarrow y=-\dfrac{13}{10}-\dfrac{3}{10}\)

\(\Rightarrow y=\dfrac{-8}{10}\)

b, \(y-25\%y=\dfrac{1}{2}\)

\(\Rightarrow y\left(1-\dfrac{1}{4}\right)=\dfrac{1}{2}\)

\(\Rightarrow\dfrac{3}{4}y=\dfrac{1}{2}\)

\(\Rightarrow y=\dfrac{1}{2}:\dfrac{3}{4}\)

\(\Rightarrow y=\dfrac{2}{3}\)