Let Margo buy x number of tiles, So total cost of tiles and tile saw at first store is,
[tex]y=0.69x+56[/tex]The total cost equation for tile and tile saw for second store (which provide tile saw for free).
[tex]\begin{gathered} y=1.39x+0 \\ =1.39x \end{gathered}[/tex]Determine the number of tiles for total cost of tiles and tile saw to be equal from both store is,
[tex]\begin{gathered} 1.39x+0.69x+56 \\ 1.39x-0.69x=56 \\ 0.70x=56 \\ x=\frac{56}{0.70} \\ =80 \end{gathered}[/tex]So Margo purchase 80 tiles, such that total cost is equal from both the stores.
