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The larger the number the warmer it is
Tiffany payed $4.22 and Tony payed $6.33. This means that Tiffany made the better buy :)
To answer this item, we let x be the first positive integer. Then, the second would be x+1. Their reciprocals would be 1/x and 1/(x+1). Then, the equation that would best represent the scenario above is,
1/x + 1/(x+1) = 17/72
Solving the equation above,
((x+1) + x) / (x)(x+1) = 17/72
If we take the numerators of both sides of the equation,
(x+1) + x = 17
The value of x from the equation is 8 and x+1 would be 9. Thus, the answer would be 8 and 9.
The fourth coordinate point would be at (1, 1). If you look at the graph, it's easy to see which point is missing. You can also tell by looking for the x and y values that don't repeat, since this is a rectangle. -6 is an x-value for two coordinate points, but 1 is an x-value for only one. 10 repeats as a y-value in two coordinate points, but 1 only appears once.
