Answer:
Hence the expression [tex]$(5x-y)(x-4)=5x^2-xy-20x+4y$[/tex]
Step-by-step explanation:
Explanation
[tex]$\begin{matrix}{} & {} & {} & {} & 5x & - & y \\ \times & {} & {} & {} & x & - & 4 \\ \end{matrix}$[/tex]
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[tex]$\begin{matrix}{} & {} & {} & - & 20x & + & 4y \\ 5{{x}^2} & - & xy & {} & {} & {} & {} \\ \end{matrix}$[/tex]
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[tex]$\begin{matrix}5{{x}^2} & - & xy & - & 20x & + & 4y \\ \end{matrix}$[/tex]