Various options: y is directly proportional to k, with x as the constant of proportionality; y is directly proportional to x, with k as the constant of proportionality; x is inversely proportional to k, with y as the constant of proportionality; x is directly proportional to y, with 1/k as the constant of proportionality; k is directly proportional to y, with 1/x as the constant of proportionality; and k is inversely proportional to x, with y as the constant of proportionality.
The greek letter "alpha" (α) for both. If x is directly proportional to y, you could say x α y. For inversely proportional, you would say something like x α 1/y, or x α y^-1, as in, directly proportional to the inverse.
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Example with numbers: Y = X2 Y = (2)2 Y = 4 ==== So if Y is ( directly ) proportional to X2 when X is doubled Y is increased four times.
x is inversely proportional to y when x = 1/y.
Generally, if y increases as x increases, this is a hint that the quantity is directly proportional, and if y decreases as x increases, the relation might be inversely proportional. However, this is not always the case. x and y are directly proportional if y = kx, where k is a constant. x and y are inversely proportional if y = k/x, k is constant. This is the best way to tell whether the quantities are directly or inversely proportional.
Various options: y is directly proportional to k, with x as the constant of proportionality; y is directly proportional to x, with k as the constant of proportionality; x is inversely proportional to k, with y as the constant of proportionality; x is directly proportional to y, with 1/k as the constant of proportionality; k is directly proportional to y, with 1/x as the constant of proportionality; and k is inversely proportional to x, with y as the constant of proportionality.
When there is at least one pair of x and y whose ratio is different from the ratios for the others.
The greek letter "alpha" (α) for both. If x is directly proportional to y, you could say x α y. For inversely proportional, you would say something like x α 1/y, or x α y^-1, as in, directly proportional to the inverse.
According to the equation [ y = 2x ], 'y' is directly proportional to 'x' .
Two variables, X and Y are said to be in inversely proportional is X*Y - k where k is some non-zero constant. X and Y are said to be directly proportional if X = c*Y where c is some constant.
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If a variable (such as y) is directly proportional to another variable (such as x), they both increase and decrease simultaneously. An equation for two directly proportional variables is:y = axIt's sort of like a linear equation, but it always goes through the origin.An example is y = 6x. Notice that it forms a straight line and crosses the origin, and that y and x increase in the same direction.
Insufficient information. What is x when y = 12?
There's no way we can figure that out until you tell us how 'x' and 'y' are related to each other. That kind of information is called an "equation".
y=54 if x=6 so we can write y=9(x) so y=k(x) clearly y is directly proportional to x.
Example with numbers: Y = X2 Y = (2)2 Y = 4 ==== So if Y is ( directly ) proportional to X2 when X is doubled Y is increased four times.