Question

Answer 1

x=7

Answer 2

\(\dfrac{13+x}{36}=\dfrac{20}{36}\)

\(13+x=20\)

\(x=20-13\)

\(x=7\)

Answer 3

\(\dfrac{13+x}{36}=\dfrac{5\times4}{9\times4}\)

\(\dfrac{13+x}{36}=\dfrac{20}{36}\)

\(13+x=20\)

\(x=20-13\)

\(x=7\)

Answer 4

\(\dfrac{13+x}{36}=\dfrac{5}{9}\)

\(\Leftrightarrow13+x=\dfrac{5}{9}\times36\)

\(\Leftrightarrow13+x=20\)

\(\Leftrightarrow x=20-13\)

\(\Leftrightarrow x=7\)

Answer 5

\(=>\dfrac{x}{36}=\dfrac{5}{9}-\dfrac{13}{36}\)

\(\dfrac{x}{36}=\dfrac{7}{36}\)\(=>x=7\)