The behavior of the y-values as the x-values increase depends on the specific relationship between the two variables. If the relationship is positive, the y-values will increase as the x-values increase. If the relationship is negative, the y-values will decrease. In some cases, the y-values may remain constant regardless of changes in the x-values.
To find the slope of a non-vertical line you need two points on the line. Subtract the second y-value from the first y-value, and subtract the second x-value from the first x-value, then divide the first number calculated by the second number calculated. As a formula, it looks like this: slope = (first yvalue - second yvalue) / (first xvalue - second xvalue) Alternatively, if you know calculus, the slope at some x-coordinate a of the function f(x) = d/dx[f(x)] evaluated at a = f'(a).
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