Operational research and Decision theory DUEN IMA 214 EN 2024 2025 2

What is the correct dual?Maximize Z=7x_1+2x_2Subject to:\begin{align*} x_1+4x_2 & \leq 20\\ 3x_1+x_2 & \leq 15\\x_1,x_2& \geq 0\end{align*}