the length of the rectangle is n-3, ok, the width is 2
the area of a rectangle is just length * width
[tex]\bf A=(n-3)(2)\implies \boxed{A=2n-6}
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\textit{to make some equivalent, let's use our good friend Mr 1}
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\textit{recall that }\cfrac{whatever}{whatever}=1\qquad \qquad \cfrac{same}{same}=1
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\cfrac{55}{55}\cdot 2n-6\implies \cfrac{55(2n-6)}{55}\implies \cfrac{110n-330}{55}
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or
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\cfrac{xyz}{xyz}\cdot 2n-6\implies \cfrac{xyz(2n-6)}{xyz}\implies \cfrac{2nxyz-6xyz}{xyz}[/tex]
so, if you simplify either of those, you'd end up with 2n-6.
because same/same = 1, and 1 * anything, is just anything itself.
