\[20x + 5 \cdot (x - 2)^{2} =\]
\[= 20x + 5 \cdot \left( x^{2} - 4x + 4 \right) =\]
\[= 20x + 5x^{2} - 20x + 20 =\]
\[= 5x^{2} + 20\]