So for graphs, to tell if its a function is to see how many points are on the x-line for the coordinate. Functions will only have one point on each x-line.
With the top left, x = 0 has 2 points on it, so that is incorrect.
With top right, x = -1 has 2 points on it, so its incorrect as well.
Bottom left has 3 points on x = 0, so that's incorrect.
Bottom right, however, has no x-line where there are two or more points on it, so it is a function.
Area = length x width.
24 = (x + 2)(x - 3) = x² - x - 6
x² - x - 30 = 0
(x + 5)(x - 6) = 0
We can eliminate the root x = - 5 because dimensions cannot be negative. So, the only valid answer is x = 6
The length = x + 2 = 6 + 2 = 8 in.
The width = x - 3 = 6 - 3 = 3 in.
Answer:
When heated calcium carbonate forms calcium oxide and carbon dioxide.