MathsDirect Proportion

Direct Proportion

Formula and explanation of Direct Proportion

In direct proportion, when two variables are related, one increases as the other increases. The most common way to represent this type of relationship is with a line graph that has a positive slope. The slope of the line indicates the rate of change between the two variables. In mathematical terms, the slope of a line is determined by the following equation:

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    m = (y2 – y1) / (x2 – x1)

    Where m is the slope, y is the y-axis value, x is the x-axis value, and (x2 – x1) and (y2 – y1) are the differences between the corresponding x and y values.

    An Overview of the Direct Proportion

    The direct proportionality concept states that the variables in a mathematical equation are proportional if the ratio of their values is always the same. In other words, the values of the variables change in the same proportion when the equation is graphed. The slope of the line on the graph is always the same, and the equation of the line is y = kx, where k is the slope.

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    Direct Proportion Meaning

    The definition of direct proportion is that two quantities are directly proportional if the product of the two quantities is a constant. In other words, the two quantities are related in a linear fashion. This constant is known as the proportionality constant.

    If two quantities are directly proportional, then as one quantity increases, the other quantity also increases. Alternatively, as one quantity decreases, the other quantity also decreases. This is illustrated in the following graph.

    The graph shows that as the value of x increases, the value of y also increases. This is because the two quantities are directly proportional. The proportionality constant is 1.5. As the value of x decreases, the value of y also decreases. This is because the two quantities are directly proportional. The proportionality constant is -1.5.

    Direct proportion definition

    Direct proportion is a definition that states that two variables are in direct proportion if the ratio of their values is constant. In simpler terms, this means that as one variable goes up, the other goes up by the same proportion. This can be represented by a line on a graph that is always straight and has a slope of 1.

    Direct Proportion Example

    If you want to know how to find the value of x in the equation y = 2x, you can use the proportion y/x = 2. This proportion can be rewritten as x = y/2.

    Direct Variation Example Problems

    1. A ball is dropped from a height of 2 meters. Every second, the height of the ball decreases by 1 meter. Write an equation for the height of the ball at any time, t.

    h(t)=-1t^2+2t

    2. The width of a rectangle is directly proportional to its length. If the width is 5 meters, what is the length?

    If the width is 5 meters, then the length is 10 meters.

    For more visit Direct and Inverse Proportions –

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